Plumbing Design/Question

[Sway70]

Recentlt picked up a 90 gallon tank.

It is predrilled with 3 holes in the center bottom overflow.

1 - 0.5” hole on the left
1 - 1.5” hole in the middle
1 0.5” hole on the right

Previously the system was setup as the 2 0.5” holes as a split return and the center hole as the main drain.

How should I plumb this setup? The same with no emergency drain or go with a herbie setup and what holes should I use for the drain/return/emergency?

I will be using a Vectra as the main return pump.

Thanks in advance

 

[sbash]

Are there bulkheads in the holes already? They seem like oddly sized holes to me if not. For example, a 1" bulkhead usually requires a 1 3/4" hole.

If there are bulkheads already, then I would use the 1.5 as the return (split it at the water surface with a dual Loc-Line nozzle). Then use the other two as a herbie type setup.

 

[Sway70]

Yeah sorry, there are bulkheads already.

Thanks for your input.. didn’t think about splitting the bigger hole.