Anybody use bottom returns on their tanks?

[runway1]

Considering adding a couple of returns on the bottom of a new 120 gal I'm having drilled. You know, through the tank floor, pointing up.

I'll have a closed loop system with two returns on top and was considering adding two more through the floor to take out dead spots. Suggestions? Thanks all!

 

[MantisFreak]

Many glass tanks have tempered bottoms and cannot be drilled. You can do this with acrylic tanks. I know someone setting up a coral prop tank in this manner.

There are some things to consider. Namely don't go cheap on the bulkheads. If you were to have a failure on one of them, your entire tank is going to empty. That's why when holes are drilled on the bottom, they are usually incorporated into an overflow. That way only the water in the overflow leaks out.