Drain and return locations in drilled tank

[wings4wheels]

I have a 6 foot long 150g tank that has holes drilled in the back glass. one in each upper corner area and one in the upper middle. I was thinking of adding 2 overflow boxes, one in each corner and using the center hole for return flow from the sump. Let me know if this is the correct, or if I should set it up in a different way.

Thanks in advance

 

[ScottieB]

Welcome aboard!
I think that sounds like a good plan. What size are the holes? If they allow for 1.5inch bulkheads you should have plenty of flow through those. I think the fijicube overflow boxes that utilize a single bulkhead can be 800gph with two of those you got way more potential flow then you need.
Another option for smaller bulkheads would be run all three as overflow boxes and install the returns over the top of the back wall. I have seen some build threads that did a really nice job with that.
Please make a build thread so we can follow along with your progress!