I am setting up my first tank. It is a used 75 gal. The original owner had his return coming from the circled part. I replumbed in order to facilitate an emergency drain. I have relocated the return. I am left with this notch. There is an identical one on the other side. It has a cover that snaps in. Can someone point me in the direction of where to get this peice, what it's called, or a diy resolution. I fear a port that large with be problematic.




