The Conscientious Reef Aquarist

Tanks, Stands & Covers for Marine Aquarium Systems

Bob Fenner

Showtime, Germany

Flexibility is the hallmark of a successful species… and reef aquarists. From the get-go, in selecting the principal components of your captive sea you set the stage for all possibilities. Make no mistakes; the picking of your tank, cover and stand for your system is crucially important. Here is a detailing of key questions and my input in putting together your basic physical system.

Aquariums: Size: Imitating Conditions of the Sea:

"How big is the sea?" So the song goes. It's huge! The oceans vastness implies features that sustain its life. Some of these you probably know very well; they are of importance to all aquarists.

Stability: Chemically and physically ocean water is quite homogeneous worldwide; about the same mix of salts, specific gravity, even temperature over the enormous span of the tropics. It makes sense that the biota there, in particularly the attached and slow-moving forms exhibit narrow (compared to unstable, puny freshwater environments) tolerance to adverse or varying conditions.

Cleanliness: Here is that "ideal"- high water quality; naturally. As with stability, the largeness of the seas and their currents and wave action continuously washing the reefs, conveying sex cells, wastes, oxygen, carbon dioxide, chemical nutrients, food and plankton, preserves consistent but dynamic homeostatic conditions. Another paradox. Water is rarely stagnant in the seas.

Dilution of Chemical and Biological Contamination: To the neophyte a less well known challenge of keeping captive reef life is the chemical and "other biological" interaction between species and specimens that is intensified by our smaller volumes, weak circulation and crowding. How many groups of marine organisms can you cite as releasers or sources of toxic substances? Species of soft corals, puffers, sea cucumbers and more are capable of selectively and generally wiping out a system.

Of consequence to the reef hobbyist is how to approach the stable, clean and toxin-diluted conditions of the real seas. Other than sparse stocking and feeding, two means of maintaining consistent high water quality in a small volume of seawater exist; maximum volume (for stability) and appropriate filtration and circulation.

Tank Size:

How large a system is ideal? Is there an upper limit? How about lower? In my opinion, forty gallons is an absolute minimum for a reef system. Smaller volumes are too restrictive in what they can support to interest me; and given to "crashing" much too easily. An unnoticed death, loss of power, a "little helper" overfeeding can mean bouillabaisse in a few hours in smaller "tiny-reefs".

Yes, there are stores, hobbyists, even other writers on reef topics who go so far as to endorse small (i.e. less than 40 gallons) systems. I think they're remiss for doing so. Take a look at the real cost per gallon of maintaining such necessarily depauperate communities. Relatively VERY high costs for lighting, filtration, livestock replacement, and labor compared with realistic size systems.

The "tank" part of a reef system is decidedly cheap in the long haul, compared with the costs to acquire other components, livestock and especially operation. Don't limit or handicap yourself; get as big a system as you think you'll ever want and space allows.

Tank Shape:

There are two elements in considering desired reef tank shape; aesthetic and functional. The first, what "looks good" should take a far second place to what "works". Functionally, reef tanks should be more flat and wide versus tall and narrow, so called "show" designated formats in the trade. "Standard" gauge systems have outstanding advantages over "showy" ones.

Set-up & Manipulation: How long are your arms? Or alternatively, is the system so gigantic that you intend to go diving in it? Some folks practically have to due to tank depth. Putting in equipment, rock and sand can be just the beginning of your body-dunking. Routine cleaning, adjustments, the at-times nightmare of attempted livestock removal… You want your system to be the epitome of "user-friendly"; shallower is better. Eighteen inches of depth is preferable to twenty-four, which beats out the practical maximum of thirty.

Likewise, wider tanks are preferable over narrower. In general I'd avoid aquariums of less than fourteen inch width; twenty if the system is to be viewed/aquascaped from both front and back. The logic of this wide-body preference is obvious to anyone who has set-up and maintained a reef tank. Rock can't be stacked, adequate space around the perimeter made for circulation and animal movement, or your cleaning otherwise.

Material of Tank Construction:

What characteristics should the "stuff" of your tanks walls have? Strong, chemically-inert, attractive certainly, allowing flexibility, and reasonably inexpensive are qualities that come to mind in choosing the material of construction for reef tanks.

Strength to resist breakage. Especially when moving reef systems are prone to splitting a seam, cracking, and breaking through-hull fittings.

Chemical Non-reactivity is absolutely necessary. Metal contamination is particularly troublesome. Any resin or epoxy must be thoroughly cured before near or underwater use.

Attractiveness: Is everyone happy with the appearance of the tank itself? This is almost never an issue once the system's up and going. With beautiful set-ups no one can even remember what "the box" looks like.

By flexibility, I'm referring to something more than whether the container will hold water. How easily can it be modified; cut, drilled to accommodate plumbing, other gear? How big is the opening to the top, or to what degree can it be modified to allow adding/removing large objects, or permit maximum light exposure?

Real World Choices: All-glass (with or without plastic "frames) aquariums should be drilled for all through-the-tank fittings before silicone assembly; cutting them later is a hassle or worse. Overflow towers of whatever material are easily affixed to their structural walls at any time.

Fiberglass and resin, epoxies and wood, polyethylene, PVC sheet… there are a number (but I don't know what it is) of variations of aquarium construction just using glass or acrylic as viewing panels, and 'other' material as the rest of the tank. Unless you have a real deal on these novel construction materials and the tools to work them, I'd still with all-glass or…

Acrylic or Plexiglas aquariums which I prefer over glass and all other materials for home-size systems for a few reasons:

Acrylic tanks are tough; some six times stronger than the equivalent thickness of glass. Far more forgiving on less-than-perfect stands or during earthquakes or bumps.

Acrylic is a better thermal insulator. Remember you have to pay to keep the system heated/cooled higher/lower than ambient.

Acrylic is easy to "customize"; it can be drilled, cut, added to with ease. This minimizes salt creep and messy clean-ups.

Acrylic tanks are clearer than glass, which weathers worse.

Acrylic tanks are beautiful with their corners either end-butted or heat bent; they're gorgeous.

Acrylic tanks are lightweight; much lighter than glass or composites. Moving them is a breeze comparatively.

For all these reasons acrylic tanks hold their resale worth high. Other tanks lose half their value when they leave the store. I have seen acrylics sell for more than they were purchased for, years later.

Yes, acrylic tanks do bow more and will scratch if rubbed or struck with something hard; but so does

glass. And acrylic can be fixed for scratches relatively easily. My advice should be obvious; buy acrylic. My number two choice, a good quality all-glass tank pre-drilled (if wanted) for water egress/ingress.

Covers:

Tank tops of several sorts are functionally useful for keeping livestock in, hands and dust out, and reducing heat and water loss by evaporation. For canopy types, lighting and more might be affixed therein. What about looks? They can be attractive as hoods and as such block the glare of overhead lighting.

Other than cost and cleaning, there are a few other problems with tops, especially covers. Unfortunately, even the best in-between water covers also block, reflect and shift the wavelength of artificial light sources. Hence, many 'reefers' eschew cover use. If you do employ them, get ones that are easy to keep clean and be religious concerning their maintenance. If you're doing away with covering your system be sure to otherwise provide for "jumpers" by lowering water level, maybe employing a rim around the edge of the tanks top, and/or lay a grid over the tanks opening. Watch specific gravity "drift". In a low humidity setting, the amount of water (and heat) lost (or gained with a chilled system) can be surprising. Get in the habit of checking and adjusting your specific gravity daily in open-top systems; or adopt an automated system to do it for you.

The biggest gripe aquarists have with covers is access. Particularly with large systems having lighting, ultraviolet shields, and air-cooling fans built in, tops can be heavy and cumbersome. If you build or buy one of these hefty beauties do arrange a mechanism (pulleys, or split the top in 1/2s, 1/3s…) for getting it up and out of the way so you can get into the system without getting burned or bruised. Oh, and do include a small access port for minor work, like feeding.

Stands:

The physical structure supporting your reef system must be level, planar, strong, and possibly roomy underneath.

Level relative to the center of gravity of the planet. Use a good carpenter's level tool, or better still, the tank's bottom with a thin layer of water to determine level and adjust with shimming the legs/base of the stand.

By the word Planar, I mean flat on the bottom. Use a single piece of something; plywood, plastic, closed-cell foam… to support the entire underside of your aquarium evenly. Unevenness and sudden jolts are your aquariums' twin nemeses. For "floating bottom" types of frame construction, common with commercial glass aquariums, and "no bottom" store-bought stands utilize the same "great equalizer" under the tanks bottom that does come in contact with the stand unless they are perfectly planar (check for light between the tank and stand or rocking).

Strong means the stand can support the force of the system on top of it as well as possible lateral forces (earthquakes, child-rocking). As a structure it should be braced in three dimensions, including attachment to walls, floor, wedging between furniture. As to fasteners, bolts are better than screws, which far outshine nails. For putting metal stand pieces together, welding is best.

Space Down Under: How much equipment (sumps, pumps, protein skimmer…), plumbing, outright junk do you intend to situate under your tank? What about the placement of electrical cords, meters, chemical dosers…? Don't fool yourself; there's never too much room underneath. Should you be designing, building your own, double the space planned. Trust me here. Getting a factory-made stand or paying someone to make you one? Pay attention to spaces, cutouts for overflows, returns, conduits for power and other electric items; You don't want to drill through your stand supports.

Close:

Take the time to think out these important elements to your reef system; this will save you tremendous headaches and money. Having the best tank, cover and stand initially not only sets the stage for your creation, but is the only way you can hope to optimize your reef experience.

Bibliography/Further Reading:

Agbayani, Nestor. 1995. Beam sizes for aquarium stands. FAMA 8/95.

Bauman, Edward. 1990. Editor's Corner: Mini-tanks, big problems. The popularity of tiny tanks maybe unfortunate for the hobby. AFM 8/90.

Bickmeyer, Walter. 1975. Build a cabinet for your fish tanks. TFH 6/75.

Birdsell, Ben. 1988. Over the counter (on DIY glass tank construction). FAMA 11/88.

Brosseau, Richard. 1992. How to build a heavy duty aquarium stand. FAMA 9/92.

Flood, A. Colin. 1987. Tini-Reef; A small tank with all the right ingredients for marine filtration success for beginners. FAMA 4/87.

Gannon, Robert. 1960. Sturdy stand for battery of aquaria. TFH 4/60.

Jonklaas, Rodney. 1960. Concrete aquariums. TFH 10/60.

Marsh, Robert. 1996. Making your own aquarium covers. FAMA 5/96.

Mayland, Hans J. 1969. The fiberglass aquarium. The Aquarium 8/69.

Miller, John P. 1995. How to protect your aquarium against earthquakes. FAMA 5/95.

Schiff, Steven J. Aquarium set-up; the aquarium. FAMA 12/92.

Simon, Robert D. 1988. From start to finish (wood/glass tank construction). FAMA 4/88.

Stime, Jim. 1998. The reef tank; So, you want to start a reef tank? Part Two, Stands and canopies. Odyssea (J. of the Marine Aquarium Society of Los Angeles) v.4:2, Feb. 98.

Vecellio, Michael. 1988. How to build a stand for the large aquarium. FAMA 4/88.

Graphics:

Stipendium peccati mors est, "the wages/price of sin is death. Here's a "I coulda, shoulda" example of what not to do in supporting even an acrylic tank. The blocks need to be placed under all corners, and evenly support a network of doubled two by fours or a substantial beam like a four by. A mistake at my friends, Eric & Tammy Rood, Ocean Pacific Tropicals, Hawaii.

Here's how to do. An example of a show set-up in Amberg, Germany. Here the metal stands are overbuilt and the tanks cushioned with a foam sheet underneath.

A real nice cabinet style stand displaying, in my opinion, the best quality commercial all glass tank manufactured on the planet (Juwel). At Tis Tropicals, Fountain Valley, California.

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