Hey everyone. I have a 125gal tank that has the overflow in the end, it was setup as a peninsula tank when I bought it. It's been setup for a year now and things are really just getting balanced out, coralline is all on the back glass and I don't want to start over but I would like to add a c2c overflow. So my question is do y'all think it would be possible to drain the water down enough to drill the holes or is there another option, and what about hole placement? I build custom cabinets and I've done carpentry nearly all my life so I think I could do the drilling.