Parasitic Diseases of Cultured Fishes: Methods of Their Prevention and Treatment: Principles

Parasitic Diseases of Cultured Fishes: Methods of Their Prevention and Treatment: Principles

By Bob Fenner

Anilocra laticaudata on a Paranthias.

I. Considerations- What is a cultured fish, parasite, disease, infection

II. Disease differences in cultured vs. wild fishes

A. Density

B. Confinement

C. Monoculture

D. General Stress

III. Immunity and the environment

IV. Disease prevention and the environment

A. Maintaining proper conditions

B. Preventing introduction of infectious organisms

C. Sterilizing water, ponds

D. Nutrition

V. General fish pathology- disease detection

VI. Treating diseases

A. Considerations

B. Biological control

C. Physical-mechanical control

D. Chemical control

E. Methods

VII. Problems in disease- discussion

I. Considerations

What is a cultured fish? Any produced, grown for food, sport or aesthetic purposes. The current list includes several hundred species, but principally involves a few dozen as most important, particularly some cyprinids, salmonoids, acipenserids, ictalurids, silurids, pangasiids, mullets and milkfishes as food fishes, and dozens of other cyprinids (minnow-sharks, barbs, danios, rasboras), characiforms (tetras), callichthyids, loricariids, several South American and African cichlids, clownfishes, dottybacks, neon gobies... My discussion will largely involve examples of these aquatic-source protein and tropical ornamental fish groups, as well as pond rather than open-water (e.g. sea-ranching) culture.

A parasite may be defined as any organism living in or on another species where it obtains it's nourishment (plant or animal) and perhaps protection.

Disease is any departure from health; for our purposes as related to infection or infestation by other organisms, i.e. parasites. Limited reference will be made to infectious diseases "caused" by viruses, bacteria, fungi, algae and parasitic diseases caused by protozoa, helminths, arthropods and other metazoa.

A parasitic infection-infestation may be:

A) Pathogenic- disease producing

B) Latent- only mildly infectious. A situation where the fish has more or less reached an agreement with it's parasites due to natural or acquired immunities. It's important to remember that many parasites, viruses, bacteria, funguses, protozoans, helminths and arthropods are very often present with a cultured fish species. If a healthy, stable environment deteriorates, dissolution of immunity follows and a latent infection becomes pathogenic (Spotte, 1973).

Diseases in wild and cultured populations of fishes by be caused by pathogenic organisms, effects of toxic materials, or general environmental deterioration. Because all three groups of these factors operate together they will be discussed together as they relate to parasitic diseases of cultured fishes.

II. Disease differences in cultured vs. wild fishes

As Bauer (in Dogiel et al. 1970) points out, there are several major differences, positive and negative, between pond-cultured and non-pond cultured fishes, their disease control and prevention. Generally the number of parasite species is lower but due to the conditions of culture their numbers may be high and disease etiology altered. These differences may be explained by consideration of the design of culture systems vs. wild environments.

A) Density- Due to the proximity of conspecifics, transmission of parasites is facilitated. Also, very little is known re the social, pheromonal effects of crowding.

B) Confinement- The uniformity of a culture environment in terms of temperature, pH, oxygen concentration, food availability, and other physical-chemical-nutritional factors allows little latitude for cultured fishes to select more suitable conditions.

C) Monoculture- The cultivation of one or perhaps a few species in a system that is periodically sterilized, otherwise chemically treated negates the presence of intermediate hosts and vectors. Consequently, most systems harbor a smaller number of parasites than natural waters. Parasites with complex life cycles, such as flukes, tapeworms, thorny-headed worms and roundworms are rare, whereas protozoans, some leeches and copepods with direct life cycles are common.

D) General stress- Disease in fishes can be a physiological response to stress (Gratzek, 1975). Some common sources of stress are transportation, excessive handling, abrupt temperature fluctuations, physical-chemical factors, and overdosing with medicants. Many fishes die outright from severe stress but many more often from chronic less-severe stresses. Many fish pathologists feel that fish carry bacteria and protozoans in low numbers in their blood and kidney tissues as well as on the surface of their skin and intestines, but remain healthy until stressed.

III. Immunity and the environment

There are three general sets of considerations to the well-being of any cultured stock:

1) Initial state of health, genetic and developmental

2) Suitability of the environment (chemical, physical, nutritional, social...)

3) Virulence of present pathogens

Fish stocks are selected and bred for traits which insure greater resistance to the stresses of culture, including disease control. Many viral, bacterial and parasitic diseases have been selected against by genetic engineering. Recently (1975) there has been established a Fish Genetics Lab of the Bureau of Sport Fisheries & Wildlife in Beulah, Wyoming (Anderson 1974).

It's been mentioned that as regards disease-causing organisms the physiological condition of the hosts determines whether they remain latent. Such factors as oxygen concentration, carbon dioxide concentration, unionized ammonia presence, organics and heterotrophic bacteria accumulation may shift the balance of health-sickness. Very often outbreaks, particularly bacterial and protozoan infections are the result of a decline in water quality or inadequate nutrition (Spotte, 1970). Pollutants are receiving more and more attention (Vernberg et al. 1977). Temperature fluctuations and high toxic metabolite levels are two most cited causes for epizootic outbreaks in established systems.

IV. Disease prevention and the environment

Most preferably and often the only way to eradicate parasitic diseases by prophylactic measures. Spotte (1970) lists four factors involved in environmental disease prevention:

1) Maintaining proper environmental conditions

2) Preventing introduction of outside infectious agents

3) Sterilizing circulating culture water and systems

4) Adequate nutrition

1) Proper environmental conditions are species and strain specific. For all factors there are optima and ranges for parasites and hosts. What is done is basic environmental manipulation to favor the host.

2) Many fisheries try to comply to the guidelines Dogiel et al. (1970) propose: that of naturally clean water of proper temperature, etc. running into and out of each system separately. Water from sterile sources is preferable, but rarely available. Often it is more economical to use other sources. The method of treating recirculating water (closed systems) described by Spotte (1970) is often used due to the unavailability of consistently good water.

A) Rapid sand filter- removes large infectious organisms

B) Diatomaceous earth- removes most bacteria, protozoans

C) Darkened storage vats- to store water for two weeks, later aerating it, causing death, lowered virulence of many parasites due to lack of hosts

D) Sterilizer- ozone or ultraviolet

Prefiltration involves a routine of chemical sterilization, drying of filters immediately after processing a batch of raw water.

Quarantine- new stocks should not be added to main systems until they have been isolated, treated by dips, inoculation, etc. and thoroughly checked to insure they are disease-free. All nets, equipment used with these stocks must be sterilized after use or used only for these fishes/systems.

Live foods- there is always a risk with live foods, even if tank raised, of introduction of disease organisms. In general it is safe to fed freshwater foods to marine fishes and vice versa, e.g. Artemia, Daphnia. Most commercially prepared foods are preferable to live or frozen from the standpoint of disease transfer.

Intermediate hosts; destruction of snails, leeches, copepods, etc. and wild fishes which may act as carriers or reservoirs is often done (Bauer 1973).

3) Sterilizing circulating water is accomplished much as described above for raw water. Generally ponds and tanks are completely dried on a regular basis and sterilized with strong bases, bleach...

4) Nutrition- a proper discussion is beyond the scope of this paper (please see here: http://www.wetwebmedia.com/feeding.htm). Considerations such as chemical balance, storage, amount, frequency and application method are important to parasite control.

V. General fish pathology

Identification of pathological signs and symptoms and their possible causes requires a knowledge of normal fish anatomy, physiology and behavior, such as habits and postures, swimming, rate of respiration and movements, color changes, feeding habits, growth abnormalities. A good review of fish pathology is Amlacher (1970) and Reichenbach-Klinke (1973).

Fish may be anesthetized or sacrificed. Procedure then is to examine microscopically and macroscopically the exterior, skin, gills, abdominal cavity, gonads, digestive tract, liver, gall bladder, pancreas, spleen, kidneys, swim bladder, heart, blood, skeleton, nervous system and sensory organs, eggs and fry if present.

A practical method of assessing stress in fishes using "stix", commercially available plastic strips applied to fish mucus to determine the presence of hemoglobin is described by Ramos and Smith (1978). Also mentioned as a chemical assay indicator in the literature is blood sugar levels.

VI. Treatment

A) Considerations- prophylaxis is preferable to treatment, but oftentimes inadequate.

Much care must be exercised when treating diseases of cultured fishes; often the cure can be worse than the disease, especially if stable environmental conditions can't be maintained. In many cases it is best not to treat animals infected by bacteria or protozoans as these losses can often be traced to improper environment. Generally the most infected stocks are removed and the problem/s corrected. (Taylor & Muller 1970).

Helminth and arthropod parasites have greater resistance to immune responses of the host and must be treated differently. Often a chemical must be applied and the culture system sterilized by drying or chemical poisoning (e.g. formalin, chlorine, lime). These infections are rare if water quality procedures are closely followed.

As usual, cost-effectiveness must be considered.

Types of controls may be divided into biological, physical, and chemical in order of preference by most workers (Mawdesley-Thomas et al. 1974).

B) Bio-controls

1) Predation- certain organisms feed on intermediate hosts of parasites. Some examples are the red ear sunfish (Lepomis microlophus) that eats snails, the protozoan (Amphileptus voracus), that feeds on other (parasitic) protozoans, Chaetogaster sp., an oligochaete worm, feeds on snails.

2) Cleaning symbiosis- known mutualistically symbiotic cleaner fishes and shrimps are used in the pet-fish interest as biocontrols.

3) Physical controls- includes such things as increasing flow rate, filtration, sonic vibrations, photoperiod and strength, pH, UV light sterilization, surgery (brood fish) and temperature manipulation. There are often differences between ideal temperatures and ranges for hosts and parasites, such that by raising or lowering one may be selected for. Anthony (1969) observed that raising temperature from 12 to 20 C. resulted in the disappearance of Gyrodactylus elegans on the goldfish, Carassium auratus. According to Lom (1969), the protective capacity of the mucus of carp infected with trichodinids is manifested only at elevated temperatures.

4) Chemical control- generally considered a last line of defense, prophylactic use of chemicals is often important in North American fisheries during March through July when parasitism is highest, resistance lower, and fish and parasite reproduction coincides. Inspection and treatment are scheduled using temperature as an indicator. (Herman 1970).

Degree of success in using a compound is related to water chemistry, temperature, pH, salinity substances with synergistic and antagonistic effects, formulation differences and methods of application; the susceptibility of fishes to toxicants is affected by their developmental stage, physiological condition, age, size and sometimes sex. Species, subspecies, and strain differences may be profound, so effect determinations must be exact (Hoffman 1974).

When selecting a medication several factors should be kept in mind.

1) The medication should be "quickly" degradable; many have residual effects.

2) The compound should be as specific as possible; few are.

3) It should have as little deleterious effect on beneficial microbes, e.g. filter bed, as possible.

4) It should cause as little stress to the cultured species as possible. Several compounds, e.g. heavy metals, cause fishes to shed lots of mucus; this should be avoided as the mucus serves several vital functions (please see here: http://www.wetwebmedia.com/fbodyslimfsh.htm); defense against invasion, attachment of ectoparasites, involvement in gas exchange and osmotic balance. Fish mucus contains parasitic protozoan repelling antibodies (Lom 1969).

5) Laws- FDA requires extensive testing of any chemical agent before it can be used on a sport or food fish. Other countries have even stricter laws.

Often used chemicals:

Formalin continues to be a mainstay for the prevention and treatment of external protozoans and monogenetic trematodes. There are lots of cautions on use re temperature, oxygen levels, etc. This material is best used as a flush.

Malachite green is the only other chemical used widely in the U.S. for the treatment of fish parasites (Herman 1970). Calomel and Carbersome are no longer widely used; they are toxic and carcinogenic. Enhaptin and Cyzine are suggested for hexamitiasis. Di-n-butyl tin oxide has replaced Kamala as a vermifuge. Gammaxine (benzene hexachloride, BHC) is used for the treatment of parasitic copepods; Dylox (Dipterex, Neguvon... please see here: http://www.wetwebmedia.com/PondSubWebIndex/contrpdparasit.htm) is preferred by others. Quinine is limited to use in aquaria. NaCl, copper sulfate and potassium permanganate are highly toxic to some species.

E) Methods of application

Diseased animals generally should not be treated directly in the culture system with chemicals. Many substances such as antibiotics and formalin interrupt nitrification, so treatment tanks use physical and chemical methods, e.g. carbon filtration, air-stripping with ozone for ammonia conversion, and not bio-filtration (Mawdesley-Thomas 1972).

Several methods of application are used. The most common method of administering therapeutic agents to fishes is bathing them in water-soluble compounds. Variations are dips, short baths (1 hour), flush (flow through), long bath or constant flow of drug. Oral-medicated feeds are widely used to administer drugs to fishes for systemic infections. Injection of large numbers of fish is time-consuming and stressing to livestock. Small numbers of valuable fish may be treated this way. Topical-wounds and localized infections of valuable fish are sometime treated with topical applications.

VII. Problems in disease- discussion

Treatment of parasitic diseases is largely limited to those occurring on external surfaces and the intestinal lumen. Blood parasites and encysted worms can't be treated effectively and economically at this time. Treatment of intestinal parasites must be accomplished orally.

There are many serious parasitic disease w/o cure. We need a drug badly in the fish industry that will treat for both protozoans and gill and body flukes for instance.

Other major deficiencies in the field are lack of people who can make accurate diagnoses, low availability of cures, and lack of knowledge re life cycles, physiology and ecology of fish parasites.

Bibliography/Further Reading:

Amlacher, E. 1970. Textbook of Fish Diseases. Transl. by D.A,. Conroy and R.L. Herman. TFH Publ. Jersey City,

Anderson, D.P. 1974. Fish Immunology. TFH Neptune City, New Jersey.

Anthony J.D. 1969. Temperature effect of the distribution of Gyrodactylus elegans on goldfish. J. Wildlife Disease Association.

Bauer, O. 1973. Diseases of Pond Fishes. Transl. by A. Mercado. Israel Prog. for Scientific Transl. Jerusalem.

Dogiel, V.A. Petrushevski, G.K. & Yu. I. Polyanski. 1970. Parasitology of Fishes. TFH, Great Britain.

Gratzek, J.B. 1976. Stress in fish. Pets/Supplies/Marketing 30:2

Herman, R.L. 1970. Prevention and control of fish diseases in hatcheries. In: A Symposium of the Am. Fisheries Soc. on Diseases of Fishes and Shellfishes (S.F. Sniezsko, ed.) Am. Fisheries Soc.., Wash. D.C.

Hoffman, G.L. 1974. Parasites of freshwater fishes; a review of their control and treatment. TFH Publ. New Jersey.

Lom, J. 1969. Cold-blooded immunity to protozoa. In: Immunity to parasitic animals, vol. 1. G.J. Jackson, R. Herman and I. Singer (ed.s). Appleton-Century-Crofts, New York.

Mawdesley-Thomas, L.E. 1972. Diseases of Fish. Academic Press, London.

Mawdesley-Thomas, L.E., K.W. Burris, J.L. Knuckles et al. 1974. Diseases of Fish. MSS Info. Co., New York.

Ramos, F. & A.C. Smith 1978. The C-reactive protein (CRP) test for detection of early disease in fishes. Aquaculture, 14 (1978).

Reichenbach-Klinke. 1973. Fish Pathology. TFH, New Jersey.

Spotte, S.H. 1970. Fish & Invertebrate Culture, Water Management in Closed Systems. Wiley-Interscience, New York.

Spotte, S.H. 1973. Marine Aquarium Keeping, the Science, Animals, and Art. John Wiley & Sons, Inc.

Taylor, A.E.R. and R. Muller. 1970. Aspects of Fish Parasitology. Blackwell Scientific, Oxford.

Vernberg, F.J., A. Calabrese, F.P. Thurberg, W.B. Vernberg. 1977. Physiological responses of marine biota to pollutants. Academic Press Inc., London.

FAQs/Input re Parasites and ornamental aquatics business:

Treatment of Ich in Retail System 11/7/14
Hi Crew,
I have a relatively new fish system (has been stocked about 6 months). It has 6 divide 70 gallon and 3 undivided 70 gallon display tanks, a 100 gallon sessile invertebrate flow through unit attached,
<... trouble. Your invert., actually non-fish system/s need to be separate>
and another 600 gallons of water circulating around in the filtration systems. For a total of about 1300 gallons. The filtration is still under construction to some degree but mostly operational. Currently I'm turning over the water in the tanks ~8 times per hour. There are two pumps with this job each pumping through their own inline 440w TMC sterilizer.
<Helps; but of and by itself won't prevent parasitic, infectious issues; nor cure them>
The biofilter, skimmer, etc are all supplied by ancillary pumps. The tanks are all bare bottom but do have small amount of porous rock to give the fish a little structure. To date, I've had one or two fish break out in Ich but showed little stress and recovered quickly without any action.
<Good>
However, I had a recent outbreak which was bad enough to treat and I think my poor management of the situation has now turned into a disaster. I have done much research on your site for many years yet still find myself struggling to understand disease management well enough to apply it effectively in our system, but want to! I've also duo of full line stores to run and my fish guys all have their own ideas of what to do and I need a
system that we can apply effectively and practically now and in the future.
<Yes>
1 week and 1 month ago... our first major Ich outbreak occurs in one of our divided 70 gallon tanks stocked with an Achilles tang,
<VERY susceptible>
indigo hamlet, dwarf lion, dog face puffer, goldbar wrasse, Toby puffer, and falco Hawkfish. All Sm to M in size and in the tank between 1-3 months or so save the dog face puffer and all except the little lion were voracious eaters and apparently hardy specimens. The tang and the puffer broke out at approximately the same time. One of my fish guys caught it quick and we isolated the tank from the system. We put an Aquaclear filter with some media from the main systems bio filter and added a heater and water circulation. We did a 3 day treatment of formalin in the tank using quick cure at the recommended dose and over that period increased temperature to about 84. The treatment at first seemed reasonably effective and we did a large water change on the tank on day 3 but kept the tank isolated and increased the heat to 86, at which point I thought Ich was unable to reproduce which I thought I had read in a text book a couple years ago but upon further research realizing may only apply to the FW variety
<Yes>
though still effective in speeding up lifecycle as I understand. Well after a week or so the tang had a recurrence and we started another 3 day regime of the formalin. The tang was lost shortly thereafter and most of the other fish broke out as well. This time around the Ich were much more abundant and effected the majority of the fish. During treatment the wrasse died but the rest of the fish pulled through and the tank went another couple weeks before my fish guys had some concerns about water quality and ongoing maintenance/reliability in the isolated tank. At this point all the fish were given a freshwater dip and moved into other tanks.
The isolated tank was cleaned with a bleach solution and left to dry before being added on to the system. It's about a week later now and I have 7 or so fish from various tanks who now have Ich, a couple fairy wrasses, a
couple blue tangs, a long nose butterfly, a porcupine puffer, and a flameback angel. The puffer, angel, 1 of the blue tangs, and one of the fairy wrasses are all new fish only about a week or so in the system. I've tried to identify probably causes and I have a plethora of options.
A. Previously QT'd fish still had Ich when they were spread (although not all
the tanks that now have the Ich have one of those fish in them).
<Highly likely>
B. New fish just brought it in on them
<Quite probable this time of year>
C. Sterilizer effectiveness waning?
<Doubtful>
D. Stress related to a couple of buggerups I made
<A contributing cause/influence>
(I did some work on the system using both pvc glue and silicone and I started running water through these components several hours later and afterward did some research and discovered that until its fully cured can contaminate the water) E. Some sort of cross contamination from nets or buckets from the previously quarantined tank.
<Maybe... what do you use for a dip?>
I considered several options including copper (The invert tank can run on its own if needed),
<Ah; thank goodness>
but really don't want to introduce copper into the system as I've heard it can persist and plague invertebrates even after using media to remove it. I thought about the same with formalin but that seemed too extreme for the
situation and the wide variety of fish in the system. So I ended up moving all the affected fish to their own divided tank (on the system) and removed the rock. From their gave them all a SW formalin bath using Steven Pro's
recommendation of .75 ml per gallon. Most of the fish bathed for about 45 minutes in well circulated tank water. I lost the flameback during the dip but he wasn't looking real great to begin with. My plan is to continue
giving the dip once daily to affected fish and continue moving affected fish to the rock free tank and scraping the walls and floor of this tank every few days. Does this plan seem prudent?
<Mmm; worth trying if this is all the facilities you have>
Aggressive enough? Should I isolate the tank again (I'd rather not, the fish didn't do great last time around and it seems the UV sterilizers may aid in treatment but do I put the other tanks at greater risk?)
<I'd re-do the plumbing... isolate the two systems... non fish to one (algae, plants, invertebrates), fishes to the other... and treat w/ what you prefer. Chelated copper if you want; a quinine compound even better>
Should I do FW bath instead of SW?
<? Yes... pH adjusted... See the SOP on WWM. Sorry; am at an airport and short on time to look up>
The SW is much easier with less room for error than the FW and there are so many conflicting reports on effectiveness of FW bath as treatment and highly variable tolerance times that it's not nearly as practical.
<Aye ya... my talk at this year's Aquatic Experience show this wknd in Chi town is about this.... Have campaigned for decades to eradicate the naiveté of folks... including in the trade>
I've also considered hyposalinity but many conflicting reports there as well from industry pundits ranging all the way from it's a bogus internet myth to it's far and away the best and most effective ongoing treatment for
commercial systems.
<Again; please use WWM. ALMOST all stores, wholesalers utilize artificially low spg (but not hypo. as a treatment; it rarely works)... a good idea on several counts.>
I know my current plan is practical enough, but do you believe its effective enough to implement as our "official system" for dealing with this problem as it occurs. Are there other measures or advice you would recommend? At what point would you consider fish safe to relocate?
<... MANY... can't do the Vulcan mind-meld (unfortunately), and there's WAY TOO MUCH to re-key. WHAT you need to know is archived on WWM. See how to use the search tool, indices>
What would be a prudent length of time to restrict livestock sales on
1. tanks that had an infection but have no further outbreaks and
2. Tanks that are on the system but did not experience any outbreak 3. Fish that have been treated and recovered
<There is no set answer here w/ any degree of confidence. Were it my shop; so few organisms involved, I'd bleach the systems; treat the fish elsewhere>
For new fish, mostly I understand FW dips are a worthwhile measure and plan on doing that in the future as well as rearranging my tanks to get new fish in their own tanks between orders both to minimize stress and limit
potential impact of disease transmission. Full QT system big enough for new fish may be in my future but that comes at a heavy cost (retail comes at a premium!).
<Ah yes. Are you attending Aq. Exp.?>
Thanks for your time and effort, not sure where I'd be without your resource,
Matt
<We'll be chatting. Don't lose heart or give up. Bob Fenner>
Re: Treatment of Ich in Retail System, plus some mgmt. questions ‏ 11/9/14
Wish I was in Chicago hearing you talk but sadly no, I'm here in the weeds.
<Ahh; home now... in S. Cal. MUCH warmer!>
Quick update on the situation is fish seem to be recovering okay using the SW formalin bath. I'm fine tuning our freshwater dip method before I go that extra step. Thus far I have am having a heck of a time getting pH to
match. My ph meter goes wacky in the RO buffered water.
<Oh yes; needs to be mixed up hours in advance of testing>
Add to that my fish system stays at 8.0. Alk is fine and I've calibrated and tested my pH monitor multiple times. So I just haven't worried about it. But getting my buffered water stabilized at 8.0 or even within .2 has been difficult to do and to test since it tweaks my tester.
Re: Separate Inverts. Our invert system is physically separated from our coral system with an aisle in between the two so I couldn't think of any way to join them. However, your vehemence was enough to inspire a little
more innovation and I think I can make it work using float switches to transfer water back and for the between the systems without the need to share a sump (our sumps and filters are all in a room ABOVE the display
systems which often necessitates some creativity (this choice was made as a last resort of a do the best we can retrofit type of scenario)).
<Yes. KEEP these two separated>
Re: Hyposalinity. Prior to adding the invert system we were running our fish system at 1.019 which made acclimation from Quality Marine easier as that's what theirs came in at, and seemed like a fairly widely accepted
good thing for us to do. However, I ran across this article http://www.reefkeeping.com/issues/2009-04/newbie/index.php at reefkeeping.com that made me feel real stupid for carrying on the practice as it was a "Newbie Myth" propagated by pet stores to save money on salt.
I will say, from an anecdotal standpoint we didn't have any issues with crypt until we started bringing up the salinity. Additionally the general response I've seen on WWM is that fish should be kept at natural sea level.
Here you mention in your response that almost all wholesalers and stores keep artificially low spg in their fish systems with good reason. Amidst my confusion, I'm gathering that it IS good for me to do as commercial
operation, NOT good for a hobbyist to do. Please confirm.
<Yes; the biz is different than end-users/consumers. I would keep all but Red Sea fishes and species that live in close association w/ invertebrates (Clownfishes the best example) at artificially low spg... for salt savings,
greater DO, reduced external parasite loads...>
Re: Sterilizers. I have these guys setup (I hope) to provide level 3 sterilization which to my mind would aid in battling even these hardy protozoa. This is according to the recommendations here, http://www.qualitymarine.com/UV-Sterilizers/T.M.C./P2---110-W-Commercial-UV-Sterilizer-(up-to-264-g) turning 8x hour and running 880w of their sterilizers in my 1000g turnover volume. Where they state Max Sys Vol of 1056 at 4x, though they recommend 7x for Marine ornamental aquariums.
<Ok>
Re: "Finding everything I need to know on WWM". All I can do is smile there. Yes it's a wealth of information, almost too vast. Over the last 12 years spent many sleepless nights browsing and searching.
<Don't like you losing sleep>
I have a couple other questions relating to management thoughts that have been percolating.
Net Sterilization:
I know you recommend formaldehyde. None of our regular wholesalers sell this without malachite green which really makes a mess. Would ParaGuard be an acceptable substitute?
<Mmm; yes; worth trying. Though, you likely can order formalin/formaldehyde from out of state>
Couple Acclimation questions:
1. Do you know of or have any sort of guide for approximate lengths fish can dip/bath. For example, Small Tetras, ~30 seconds vs. Tangs 60 minutes etc. that I can use as a starting point for staff getting this figured out?
<Not really... is an individual "guess" per species, sizes, apparent state of health... Better to under-time than over, AND always be present, observing while>
2. Currently our acclimation process is simply neutralize ammonia in shipping water with prime and drip acclimate until pH of shipping water matches tank water. I've been studying up on the Guerilla method and your acclimation power point presentation. Is a video of you presenting this available anywhere?
<Ahh! There will be very shortly. Tiff recorded my presentation this weekend for this purpose. Thank you for asking>
I did not find it on YouTube. If not, I'm going to have some questions for you but I'll keep them pending.
Markup:
What's your analysis of a good markup for marine aquarium livestock.
<For inexpensive livestock (e.g. most damsels) three-four hundred percent... most all three hundred, expensive species (tens or more dollars cost) doubling>
I'm just crunching some numbers in my head and it seems that if I were to be doing this in the best way possible, I'm going need to mark up my already expensive (MAC Certified and SSC) livestock a lot more. If I distribute the cost of ordering, shipping, and receiving, quarantining, and moving livestock in batches of say $1000 at a time (which I'm estimating at about 30 hours per order from preorder > ready for sale)... if I price even close to my competitors, then I'm giving away the fish.
<All too common in our trade>
Granted, its still probably a better way to go as giving away the fish is better than killing the fish. Do I just need to get this system down to such a degree of perfection that it's easy-peasy. Is this just the way it has to be to earn dry goods business?
<Some folks have argued (myself included) that the livestock really does just drive dry-goods sales... and that the latter pay the bills. There are a few (not many) shops that make money selling fishes, invertebrates, plants... but not much>
The problem there is that my dry goods margins are shrinking like crazy as ecommerce grows. I saw Bulk Reef Supply mention in a YouTube comment on a MACNA talk recently that the industry is moving to a 30% standard margin and that retailers aren't setup to survive on that.
I'd say he's definitely right.
<I wholeheartedly agree. I WOULD NOT offer/sell anything that you can't make/clear a forty percent NET margin on... overtime otherwise you will go broke. Our own stores gave up selling tanks, stands, canopies, some
lighting, pump, filtration lines as others locally (LFS!) were giving these away. No sense>
I guess I'm rambling beyond the point of productivity here... so I'll let you go.
Matt
<Cheers, Bob Fenner>

commercial holding tank questions; Crypt... 5/16/13
Hi Bob,
It has been awhile since I last wrote you so I figured I would check in as I had a few questions I am hoping you can answer. Last time we spoke I was about to open my new saltwater shop and you were helping me figure out my issues regarding ammonia spikes with the new dry rock and instead adding the fresh live rock to the set up in the fish holding system. I'm happy to say that business has been really good since opening and I have been busier than I could have ever expected to be honest in my first year.
<Ah good>
I am so busy some weeks that I have trouble keeping up with getting new livestock in to the shop after everything is sold on busy weekends. Which leads me to my questions. If you recall my store consists of a 1000g fish holding system and a 800g coral/invert system. The coral/invert system does fantastic. I run a skimmer and ozone and dose supplements for the corals as needed. No problems there. The fish system however has been a headache from the start. No matter what I do I can not seem to get things the way I want them. If you remember I have a centralized system of 24 x 40g breeder tanks with an inch of aragonite sand
<I'd switch to coral sand... for looks, function; though not really a giant step forward here>
and one or two live rock pieces for each tank. One 3ft LED strip light on each tank. In the back I have a 150g sump
<Is there room to add volume here? I would>
with a commercial sized protein skimmer, an Ozotech 1g ozone generator, and a Emperor Aquatics 300w HO UV along with 900w of heaters. Salinity is kept at 1.022-23. Temp: 74-75 in the winter months, 76-77 currently in the spring months as the retail space is on a concrete slab floor which stays cool. No ammonia, nitrites, <10 nitrates. I have also been corresponding with Bob Goemans regarding my current utilization of Chloroquine phosphate through the holding tanks as I have had good luck in the past using it in a hospital tank setting.
<I do hope/trust that you're not using CP on a continuous basis>
My question in essence deals with disease prevention. Every time I get a new shipment in of fish I see crypt spots pop up on the tangs and angels within a few days of arrival.
<Ahh, very common... the rule rather than exception>
I was hoping running the CP through the holding tanks at 10-15mg/l would prevent this from happening
<Mmm, no... copper would be an order of magnitude better>
but it does not seem to be as effective as I hoped. I am not sure if the rock and substrate are effecting the effectiveness of the drug or if the tank lights are degrading the medicine or even having an effect at all. I turn off the ozone and UV when medication is present.
<Yes; have to>
And have been redosing every 5-7 days as directed by Ed Noga and Bob G. I have tried the Guerrilla acclimation technique and have been ordering from reputable wholesalers (QM, SDC) without much luck in preventing outbreaks on new arrivals of certain Ich susceptible fish.
<You likely have a resident infestation... Are you "up to" the possibility/practice of bleaching the receiving/holding/isolation area every shipment? Moving some clean filter media from another system (perhaps the invertebrate sump)? Otherwise... I might stoop to the use of a chelated copper product in your fish system>
I am thinking in going a couple different directions at this point...
1. Setting up a three level QT rack in the back room big enough to hold 30-40 fish upon arrival. Treating fish as needed for 1-2 weeks then moving up front to displays.
<Yes...>
2. Pulling all calcium based live rock and sand from fish system and replacing with bio balls, faux ornaments, inert freshwater gravel so as medications are more effective and I can treat fish system with copper or formalin if necessary.
<Ah yes>
3. Adding more UV and Ozone to the system in hopes that better sterilization will be achieved without medications.
<What is your RedOx/ORP currently? I'd keep it (safely) consistently under 400...>
My concern obviously is once the fish have visible spots or symptoms in the retail holding tanks that they are no longer a sell-able product and the shop loses money and time treating and rehabbing the fish.
<Yes; not practical>
I guess my question then would be what is your preferred method for keeping a fish system healthy in appearance.
<As you've done and stated: Have stable, optimized holding facility, buy initially clean stock, quarantine/treat if necessary enroute to offering for sale...>
I do not want to over medicate but it seems my ozone and UV are not enough on their own. Perhaps I am undersized?
<Perhaps; a factor is volume size for sure... but only "a few percent" of your issue/situation. Again, like most all shops, you have a resident/in-place parasite situation>
Other stores in the area run inert substrates and fake decor in their fish systems. I am positive the one store uses formalin in the system when adding new arrivals and then UV there after.
<I'd use the formalin only in (heavily aerated) dips, short immersion baths>
Their fish always seem to look in good health although I do hear they have high initial losses. I am worried that my live rock and sand is harboring a lot of the disease. I would like to keep some sort of substrate and decor in the tanks as I do promote reef tanks and Fowlr as my main selling setups.
Any input you think would be helpful I would be glad to consider at this point.
Thanks again Bob!
<Though it can become a "bad habit", I'd lean, direct you to try the copper route (testing for and adjusting daily) at this time. Going forward; when you and your market will pay for it, separately holding incoming livestock shipments... Bob Fenner>

Alternative treatment for a common marine parasite... Commercial Crypt remedies, prevention - 07/19/08 Hello, I was wondering if anyone on the team has had any good experience with giving a marine fish with crypt a freshwater bath in place of a more 'solid' technique, such as copper treatment or hyposalinity (not that hypo is Bob's favorite)? <Some folks report success with such... perhaps their trials involve fishes with only superficial infestations... maybe these are principally only symptomatic...> I'm more of a Cupramine guy myself (in a separate treatment tank), but it seems my employer would like me to use freshwater baths exclusively in the main display / selling tanks which also house invertebrate life. <Mmm... I strongly suggest that they, you do a bit of further considering here... I would do FW baths on arrival (pH adjusted, with formalin if a commercial setting)... and even better to best, keep all incoming fish livestock quarantined for a few weeks before showing, offering it to the public... I would NOT mix fish and invertebrate livestock in a wholesale or retail setting... period> No option for separate treatment in a different tank. So while not my favorite option it will probably still give results and just wanted to fine tune it with some input. If you could tell me your frequency of the bath, duration of the bath you find effective. <Won't be... like the idea of invading countries, murdering their citizens to "make people free", this idea is contrary to reality. How to put this another way... it won't work> And if you combo it with gravel vacuuming - water change, the frequency and percentage of water changed. If you use any other methods with it such as melafix <... API should be sued back to the stone ages for this and other faux products and their promotion. Really. Have stated this often and loudly enough. This product is garbage> for bacterial infections of crypt wounds or cleaner gobies / shrimp to lending a helping hand, or anything else which might contribute to a recovery. <All this is gone over and over on WWM> I was considering fw bath repeated daily for 14 days, <... no... too much time, trouble, and stress on the fish livestock. Ridiculous> 7 min duration, gravel vacuuming bottom of tank 5 gallons out of 60 every fourth day or so, melafix dosed daily, <Please...> few cleaning shrimp there for luck. <Don't rely on luck...> Considering use of a U.V. sterilizer instead of melafix, but not likely. Trading out treatment of secondary infections for a unknown increased destruction of the parasites free swimming stage. experience and suggestions appreciated, and thank you for your time, Jonathan <Thank you for sharing Jonathan. A note to browsers through time... this is actually an indicative case, window into the thinking, operation of the trade... A reminder that many folks, though honest, of good intent, don't really know much re the science of actual husbandry of ornamental aquatics. Bob Fenner>

Commercial system question... set-up, disease prevention... 7/18/08 Thank you for your time and patience and answering my questions. <Welcome> I own an retail aquatic store and we run the MARS systems with the large commercial bio-wheel and UV sterilizer. <Am very familiar> We are continually getting outbreaks of ick mainly. <Mmm, much that could be stated, suggested... the MARs systems "aren't that great"... in terms of stability, ramp-up-ability, disease-control/prevention... I would do some long/hard thinking re adding to here... at least particulate/mechanical (yes, unfortunately, filter cartridge addn. here now)> I know we should have a quarantine system, but our store is packed from wall to wall with items and no room at the current time. <... Life is a series of compromises... are you aware what you're trading? Through time?> Future plans will have one placed in a new location. <Ah, good> All of my wholesalers keep their salinity at 1.018 to help fight parasites <Or forestall losses... save money on salt...> and that is what we have been keeping ours at. However, we are having some high loss rates on our saltwater fish and my staff is saying that it is because of the low salinity. <Could be a contributing factor, but not likely in the top three influences here...> All of our other readings are great. 0 nitrates and nitrates, ect. We just keep the salinity low to help out. Is this causing our fish to have problems? <Again... in a very general sense, yes... but other issues, factors are more important. Primary is likely "just stress"... continuing from the rigours of collection, holding, shipping, starvation, "burn"... Do you want to "chat" re these? Their alleviation? Much of this can/could be addressed through "quarantine"... along with optimized acclimation protocol... variable by species-groups...> I have read before that they could do fine at this level for up to 6 months, but with my staff complaining, I would like to make sure. <... educate yourself> Another option that we tried in one of our systems, was run SeaChem Cupramine at low levels, and tested regularly. <Is another S.O.P. that is common in the trade... Not the best/better route to go...> This seemed to clear the ick immediately, but then after time the fish seemed to get secondary infections of some sort, loose their color, etc. Just trying to find the best approach. <Ahhh! Is stated... in WWM, other efforts in print by myself, others... Careful species, specimen selection, adequate acclimation, isolation of new stocks... Stable, optimized environment (including not-too-low SG)... Again, if you'd like we (you and I) can discuss how you might investigate these possibilities... Do you have time to visit out either in the west (LA) or the UK... I would have friends in the trade give you some one on one instruction. Bob Fenner> Thanks Brian

Re: Commercial system question 7/18/08 Wow, thanks for the quick response. Yes, I would love to chat with you more about this. Unfortunately, with the summer slowdown, and our recent expansion into fresh water fish, my budget doesn't account for a trip to LA or UK at the present time. But if we can chat another way, I would really appreciate it. <Oh yes... through here, the Net, email is fine... not as fast or instructive in a short experience perhaps, but useful> I've always understood that dry goods is where my money is at and the fish were break even, but I'm not even reaching the break even point yet! Thanks Brian <And... someone has to offer, sell livestock... and, this is your life as well... BobF>

System for Fish at new facility ( Emergency) 8/28/05 Hi Bob and Team <Hello> This is a desperate cry for help.....I have previously written asking for advice on my system for livestock (fish) <I recall> I thought I had it made....following all your guerilla acclimation procedures.... had minor cases of ich and Velvet but got rid of those effectively, and had no problems with them since....... Now I have the Mother of all major problems.....I have over 50 Queens, French, and some additional red Sea fish in stock......I have confirmed that ...I have a bad outbreak of Brooklynella <Through what observation, tools?> ......I sort of identified it a few days ago, and we have been doing 8 minute pH adjusted Freshwater baths with Formalin... <... and moving the dipped/bathed fishes to another non-infested system...> also added Methylene Blue today to the dip.......but.....I am super concerned about the next 48 hours. I removed all Cupramine with Cuprisorb....changed 50% of the water.....I possess 3/4 of an ounce of 37% Formalin...and the supplier is closed till Monday......hmmmm It's late at night here, so I hope I didn't make the wrong call by adding the Formalin to the system ( 1250 gallons)... <Very dangerous> I guess it is way below the recommended dosage for hospital tanks, and I also know you don't recommend it in the display tanks....Is there anything else I can do???? <... not enough data... re your systems...> I have some Hospital tanks, but not sufficient for all of these fish.....They are still eating , but less...are really twitchy, and today was the day they became pale. <Very bad> I used to deal with Ken at Yankee Divers, and got great fish from him...He was just about to let me in on how he had used Formalin for years, starting with very, very small amounts... <Very small> in his main system....Anyway, he sold out to a guy who has since lost me more money than I would like to admit by sending sick fish, and incomplete orders.....He also sent me 50 Turbid Flames, on the one day I was off work this year......and they spent 24 hours in my system....half were dead by then, and the other half I ordered dead ( feel guilty, but didn't want to prolong their agony).. That was a month ago...my Brazil shipment arrived 2 weeks ago. Anyway Ken said that his Bio-towers had over time become "immune " to using Formalin.....is there any truth in this? <Some> ...and....what can I do, if anything now?...as I am in danger of a big die-off in the next 48 hours looking forward to some solid advice.... JD <... we need to "start at a/the beginning"... know what you do on receiving, your systems... At this point, I would increase aeration, circulation to the maximum... NOT put any more formalin in your systems, monitor ammonia... be ready with water to change most all out... Get a microscope! BobF>

Re: System for Fish at new facility ( Emergency) 8/28/05 Hi Bob....thanks for the swift reply.......Observation?....well I have some books on the subject, and also spent a long time reviewing your site and others....The fish started scratching a little a couple of days ago, but only around the gill areas....the other signs were the twitchiness, followed by this scratching, a white mucus forming on 1 eye, followed by listlessness, losing their appetite, the whitish areas appearing, and now the "looking for air"......Also, the failure of Copper to do anything positive...... <All indicative, especially the last... though there are still a handful of genera, species of protozoans this might otherwise be... real trouble...> I have sufficient room for a couple of dozen fish in Hospital tanks, but not 60 or 70 My water parameters are perfect, and monitored every day. <I suspect/ed as such... the problem is the state of the folk's ahead of you... what were their systems like?> And I do have 800 gallons of water on standby, as well as Seachem AmGuard concentrate. All the details of my system are in the attached emails <Good> I certainly shall have to get a microscope.... <Yes> Do you have any ideas what would be a good thing to do now?? JD <Yes... add aeration, lower specific gravity... a few thousandths a day by adding freshwater... to about 1.017-1.018 (almost always a good change with marine parasitic infestations), look into that microscope, Ed Noga's works... Bob Fenner>