I know it's not ideal but would a 65 gallon (36x18x24) be able to house 3 rb piranhas for life? I was given them short notice and they're about 2.5". I have 2 canister filters on the tank now. What's the best way to setup a tank like this? I have driftwood and I built caves out of rocks which they don't seem that interested in. I want to add a powerhead but not sure how strong it should be.