LOL, Sorry for a lack of clarity, yes I meant tank size. I too have a 90 and I wasn't sure if yours was. I would like to really do something different but if the Oscar doesn't rip things up, the pleco takes a crack at it and not to be outdone by the other two, the pink convict has to get it's licks in! So other than some gravel and a piece of driftwood the tank is pretty bare.