one or two would be all you could fit in there. the general rule is a 10 gallon tank for a pair, then 5 gallons for every additional pygmy. also the ration should never be two males in a colony, unless of course it is a very big tank. it should be heavily planted for 1) a good humidity reading and 2) because the are chameleons that obviously live among leaf litters and debris. a small schefflera arboricola is what my pygmy seems to enjoy and spends 99.9% of her time. i also have an asparagus fern that grows awsome with a 2.0 uvb or a plain 6500K bulb. I use a 6500K because it is greatly cheaper than a 2.0 and has pretty much the same output. hope this helps. message me if you want to know anything else!