Drilling and Hole Size

dubmaneh

New member
I am about to upgrade to a 65g mixed tank and ordered an overflow kit from Glass-Holes. I have used their product before and am comfortable with drilling but I think I may have gone a bit overkill on the drain size I ordered.

I received their 1500GPH kit which consists of two 1-1/2" bulkheads. Meaning two, 2-3/8" holes in the back of the tank. Will this weaken the tank too much or is it ok? Has anyone done this before with success or disaster?

Just seems like taking out a awful lot of glass from the tank. Thanks in advance.
 
Thanks. Funny enough, Im building my stand off of your template so thanks again!!

The holes will be 2.5" apart and at least 2.25" from the top and sides.
 
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Just to be clear, the glass you leave between edges and holes or between holes should be equal to the diameter of the hole you drill.

That means no two holes of the same size should have less than one hole diameter worth of glass remaining between them once they are drilled. That means center-to-center, they are 2X the hole diameter apart. For an edge that means center-to-edge needs to be 1.5X the hole diameter.
 
The holes are already cut in the overflow so I would guess that they are positioned properly, but I will measure just to be sure. Thanks again for the info. That was exactly what I was looking for.
 
I am about to upgrade to a 65g mixed tank and ordered an overflow kit from Glass-Holes. I have used their product before and am comfortable with drilling but I think I may have gone a bit overkill on the drain size I ordered.

I received their 1500GPH kit which consists of two 1-1/2" bulkheads. Meaning two, 2-3/8" holes in the back of the tank. Will this weaken the tank too much or is it ok? Has anyone done this before with success or disaster?

Just seems like taking out a awful lot of glass from the tank. Thanks in advance.

Overkill? It depends. It may be listed for 1500gph, but you won't get past ~700gph, before that thing starts driving you crazy with noise. Durso is a durso, regardless of how, or where, the air enters the line. I have not yet run across a commercial overflow that is not horribly overrated. The Glass-Holes overflow is a nice little setup, but physics are still physics.
 
I have a 3000gph internal box from glass holes. I only push ~750gph and if I don't clean it periodically it gets noisy. Just had to do it today in fact. I couldn't imagine pushing even 1000gph through it. So no way I would want to try 700 gph in their 1500 model. I feel like I'm pushing the 3000gph model at my much lower rate.

Mind you I'm very picky about noise. So if noise isn't an issue push away.
 
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