Yea, are you on a first or 2nd floor? the tanks are going to be all maintained individually? You're asking for troubles surely. And if you're upstairs you better hope that floor can hold all them tanks. Sure 20 gallons is only 168lbs then add in decor, gravel and stands its more like 200lbs for a 20gallon setup. X (____) that's going to be well over 2000lbs of water around that room. Maybe more if you're running more than 10 as a low number of 20 gallon tanks. Be careful so you're fishroom doesn't end up in someones living room.