If its just going to be a hiding spot for the in-tank equipment then there should be no need to totally seal it. On the other hand, you could create a sort of overflow/sump out of it by sealing it off. If you choose to just make it loose fitting, I'd suggest making an arragacrete panel(s) that would fit the tank.
__________________
I retired and got a fixed income but it's broke.
Ed
_______________________________________
50 gallon FOWLR, 10 gallon sump.
130 gallon reef, 20 gallon sump, 10 gallon refugium.
10 gallon quarantine.
60 gallon winter tank for pond fish.
300 gallon pond with waterfall.
|