Nano Tanks: The best of everything in a tiny space

By Roy Corrigan (Mavvy)

I used about half a cup, maybe a little more, of Tahitian Moon Sand as substrate, and it's getting regular dosing of Flourish Excel and Flourish Comprehensive...about three drops each, daily. Also regular weekly 30% water changes, using a turkey baster. There's 10 watts of Home Depot halogen shinin' down on that puppy, and plenty of airflow to keep it cool. The bowl is from one of those so-called "betta spheres", approx 1 liter
©Roy Corrigan


A twelve-ounce planted...riccia on plastic net covered by Tahitian Moon Sand, and a java fern
©Roy Corrigan


Homemade lightbox/stand
©Roy Corrigan
The term 'nano tank' can best be defined as a tank of around five gallons more or less, preferably housing both flora and fauna. (There are saltwater nano tanks-but for the purposes of this treatise, we'll concentrate on freshwater planted nano tanks.) I have tanks running from 2.5 gallons all the way down to twelve ounces (in those ubiquitous 'betta bowls'-yes, they ARE useful), and all of them planted, most with fish or other critters. And you aren't limited to items initially sold as fish tanks-more later.
Containers: Tanks of 2.5 gallon size-my favorite-are made by both AGA and Perfecto (this one is sold by Petsmart under the TopFin label, and is about ten dollars). You can either use the glass canopy that comes with these or have one cut from Plexiglass at the local largebox home-repair store (Home Depot, Lowes, etc.), which usually works out better for cutting slotted areas for filters, airlines, and the like. BUT...you can also use betta bowls, larger crystal brandy snifters, acrylic garbage bins (this was one of my favorites)...the possibilities are extremely varied.
Substrate: I find my favorites are Tahitian Moon Sand, Flourite, and (believe it or not) Schutz Aquatic Plant Soil. Use an amount visually pleasing to you...rinse it well...and again...and again...and...well, you get the idea.
Plants: This is only dictated by the actual size of the container. In the 2.5Gs, I find that Java Fern, dwarf anubias, Java moss, Christmas moss, riccia, dwarf hairgrass (which has the propensity to overgrow the tank, turning the carpet effect into more of a wheat field look) and other dwarf species, fit the bill well. The best is the plant that doesn't require a substrate, and instead is fastened via thread to items such as small pieces of driftwood or inert decorative stone or lavarock atop the substrate. You may need to prepare to prune on a regular basis, even on these little tanks. Some plants can grow emersed as well(that is, the foliage can survive out of water). Makes for a purty setup.
Filters: I've standardized on the AZOO Palm filters, on those tanks that I DO filter. Non-filtered tanks simply mean more frequent water changes (turkey basters work well!) and/or less animal life. Having said that, I believe a small air-driven filter should work well, at least on tanks that aren't having CO2 injected. (Do I do that...inject CO2, that is? Most assuredly, on several occasions. I've simply scaled the DIY bottle down to a one-liter size, and use an airtube and airstone directly under the Palm's intake tube. Dunno about anyone else, but this works fine for me.) You WILL need to cycle the tanks if you plan on having animal life, by the way, just as you would a full-sized tank-don't skimp on the safety and well-being of your fauna, and cycling is covered elsewhere.
Lighting Conditions:
I've used everything from Jebo 26W units on the 2.5s with highlight plants and CO2, to Coralife 18W units, to a 25W quartz-halogen desk lamp, to a 10W Home Depot unit in a home-made cabinet...to no artificial (other than ambient) room light on a twelve-ounce-sized tank (with riccia and Java fern). Oh, and cheap timers are great. Just make sure they'll handle a three-prong 'grounded' outlet. (Hey, I'm trying to make this as simple as I can for you!)
Fertilization: I'm rather partial to the Seachem 'Flourish' line..especially Excel (for the tanks without CO2) and Comprehensive. I use a drop (about) of Excel per sixteen ounces of tank size daily, and Comprehensive in the same amount three times a week. It works well for me and any algae stays at a bare minimum.
Fauna: I like bettas. I ALSO like heterandria formosa, Florida flagfish (for the errant algae problem), guppies, and both ghost and cherry shrimp. Low bioloads. Try to use the one-inch-of-fish-per-gallon rule (excepting the hets and shrimp). I feed lightly, once daily, except Sundays, when I skip the feeding.

The 2 gallon acrylic trash bin tank ©Roy Corrigan
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An example: (shown left) I found a two-gallon acrylic garbage bin at a container store. I used an inch of Tahitian Moon Sand, a Piece of driftwood with Java fern attached, some spikes of a dwarf type of grass, a banana lily, my favorite betta Fred, a Florida flagfish, and two cherry shrimp. Add a 'seasoned' Palm filter and a 25W desk lamp..voila! A neat little biotope atop my desk. (The cherries, incidentally, are breeding.)
With a little forethought and planning, your mini-aquatic garden can be as satisfying as any larger aquarium. You'll find youself getting lost in the little world you've helped create, and you're only limited by your imagination and the boundaries of the plants and fauna selected. Enjoy! (and, if you have one of these in your office at work, beware...you'll have problems keeping people out...)
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