Well lets see. I have a 10gal, a 5 gal, and 2.5 gal on my kitchen counters. A 55 in the living room another 10 gal down the hall and 2 betta double hexes in the kitchen window. I am about to get another 55 which can go in front of where the fire place is. This is Arizona we don't need no stinking fireplaces.
? 
