When I first discovered apistos back in the early eighties, standard ten gallon tanks were pretty much accepted as the way to go. I spawned A agasizzii, A. bitaeniata, and A. steindachneri in tens. I spawned Nanacarra anomalas in a five, but the female was really hard on the male, so I switched up to a ten. Ialso spawned Psuedocrenilabrus multicolor (Dwarf Egyptian Mouthbrooders) and a trio of Apistogramma borrelli in tens. For space conservation I turned the tanks sideways and stacked them 9 across on an eight foot rack. I cut my own custom glass lids so I could still open them from the end facing me, and get lights to sit on top when I didn't have them mounted under the rack above. The biggest problem with sideways is the females like to get back away from the front with their fry, and usually also spawn in the back where I can't tell. My current cacatuoides spawn easier in a 20, and I may switch them back, but they will do it in a ten. My approach to maintaining good water quality and water parameters using small tanks is to get 55-gallon plastic pickle barrels, and treat the water in advance of doing my <regular> water changes.(note: regular- as in 10% every week). That way I have the correct water parameters for pH and hardness before the water goes into the tank. I have seen 20" flourescent strip lights by Perfecto, O'Dell, All-Glass, and Penn-Plax. Stacked sideways, you can use overhead lighting suspended above the tank. Bob Dixon