Prepared Algae for Freshwater Fish (RMF, am I quoting you right here?) 12/07/08 Hi everyone, this question is for Neale. Other than the odd nibble here and there, I've never noticed my fish eating algae. In order to up the algae intake I was wondering if Ocean Nutrition Pygmy Formula would be safe for them. The first ingredients on the package read: Tropical marine algae (Caulerpa, Ulva, Hypnea, Gracilaria), kelp. The alternative is to feed Formula Two which has spinach as a main ingredient. Would either or both of these be safe to use on a regular basis for freshwater fish such as mollies, platies and swordtails? <Both absolutely fine for freshwater fish. Unlike the situation with meaty foods, where in some cases, there are some foods best reserved as marine foods for marine fish, plant foods don't seem to work that way. While Bob would (does) argue marine algae are the ideal for marine herbivores, he doesn't say (as I understand it) blanched spinach or whatever is necessarily bad for marine fish, just not so good. <<Mmm, actually, spinach can be bad for marines... if fed too much... some metabolic consequences... and want to make my usual statements re the nutritional value of same to marines (low) and likelihood of introduction of unwanted nutrients (high) and possibility of pesticide residue... RMF>> The reverse is certainly true for freshwater herbivores, which will happily take any soft greens of whatever type. The difference between meat and vegetable foods is that while freshwater and marine prey animals have different types/amounts of various chemicals, particularly lipids (oils, fats, waxes) -- plants and algae are all much of a muchness. The only big difference is in the amount of cellulose, with terrestrial plants having the most, aquatic plants having much less, and algae the least. When you blanche lettuce leaves and other plant foods, you break down the cellulose, making it easier for the fish to digest them. This is a very long way of saying that it doesn't really matter much, and you are free to try out whatever you want!> Also, I am very curious what you use to feed your fish. <I tend to use algae-based flake and wafer foods for my herbivores. Livebearers are normally kept in tanks where algae is allowed to grow rampantly, for example my fry-rearing tank is on a windowsill than gets full sunlight for 3-4 hours per day, and consequently there's lots of algae there. The fry mostly eat that, topped off with flake food once or twice a day. I believe the flakes I use are the Nutrafin algae flakes, and the wafers are certainly the Hikari ones. I like Hikari foods generally, and find them readily accepted by the widest variety of fish. Other plant foods used include cucumber, courgette (zucchini), broccoli stem, carrots, potatoes and Sushi Nori. The "crunchier" foods are for my Panaque catfish; she also eats wood. The other catfish (Corydoras, Aspidoras, Synodontis and Rineloricaria) mostly eat Hikari algae wafers and bloodworms; I can't stress too strongly how important algae and plant foods are to catfish, with most Loricariids and Callichthyids consuming significant amounts in the wild. Cichlids are also major league algae-eaters, even things like Kribs that hobbyists mistakenly believe eat insect larvae and the like in the wild. They are in fact most sediment sifters, consuming algae and other tiny organisms. Much cichlid sickness certainly comes down to poor diet choices, lack of vitamins, fiber; cf. disease among marine herbivores such as Surgeonfishes.> Thanks! Lynne <Cheers, Neale.>

Re: Prepared Algae for Freshwater Fish (RMF, am I quoting you right here?)  12/8/08 Hi Neale, thanks for your reply! I also got Bob's note. Just to reiterate, both are perfectly safe to use daily on the freshwater side? <Yes; freshwater fish seem to have much less trouble with saltwater foods than vice versa. In fact many of the foods (probably most) we give freshwater fish come from marine sources: fish scraps from saltwater fisheries, marine algae like Spirulina, krill, etc. So by all means offer whatever saltwater algae and invertebrates you want to your freshwater fish. Mine routinely eat krill, squid, mussels, prawns, etc.> This actually surprised me to read. I thought that marine protein (herring, salmon, halibut, krill, plankton, mysis, Cyclops-eeze, etc) were excellent for freshwater fish, and the concern was just how much or little to feed based on if the freshwater fish were carnivores or omnivores. Are there anyone's in particular that are good for freshwater fish and ones to avoid? <Nope; they're all good! The best rule for feeding freshwater fish is exactly the same as for feeding humans: everything in moderation. Dietary problems tend to come from a lack of fibre, or excessive thiaminase and fat, or fish becoming hooked on just one or two foods. But if you use a variety of foods, and offer each of them sparingly, you'll be fine.> Thanks to both of you for your replies! Lynne
<Cheers, Neale.>