How low should overflow box be

ElectrumGuy · Apr 15, 2016

Hi,

I am installing a bulkhead mounted overflow box in my system. The bulkhead is 4 inches below the rim of the tank. The sump is a 55G. How low (from the top) should the overflow box be? I understand how low it is will determine what the waterline is. I have been told it should be roughly 1/4 inch from top, but I wanted to confirm this.

ElectrumGuy · Apr 16, 2016

Bump.

redfishbluefish · Apr 16, 2016

What overflow do you have? I know with a Glass-Holes, and if you have a tank with a top plastic frame, you install the box just below the frame. I have a frame-less tank and installed my Glass-Holes 3/8 inch from the top edge of the glass to the top of the overflow.

ElectrumGuy · Apr 16, 2016

redfishbluefish said:
What overflow do you have? I know with a Glass-Holes, and if you have a tank with a top plastic frame, you install the box just below the frame. I have a frame-less tank and installed my Glass-Holes 3/8 inch from the top edge of the glass to the top of the overflow.

My tank is trimmed. here is the overflow: http://www.ebay.com/itm/Bulkhead-Mo...-Skimmer-Up-to-200-gal-Aquarium-/321221623646

redfishbluefish · Apr 16, 2016

Here's what I'd suggest.....hold the overflow up to the frame, and now drop it down about a 1/16 of a inch. This 1/16 is a little play just to make sure it will fit properly. Using a Sharpie, on the back side of the glass, trace the hole location of the bulkhead. That's where you drill. Note the hole you trace will be larger than the drill bit. Determine the center and drill away. I prefer using a drill guide that also acts as the reservoir for the water to cool the bit. Starting a glass drilling bit without a guide requires considerable practice. JMTC.

redfishbluefish · Apr 16, 2016

Oops! I just realized that this overflow doesn't have a hole(s) predrilled in the back. Now I see where your question is coming from.

I'm going to take a leap of fate and assume there are no baffles in this overflow. Glass-Holes have baffles and the bulkhead hole pre-drilled. If no baffles, I believe you'd want to set this up as a ghost or Herbie. Sorry, I can't help you, but there are loads of DIY threads on installing these kinds of overflows.

ElectrumGuy · Apr 16, 2016

redfishbluefish said:
Oops! I just realized that this overflow doesn't have a hole(s) predrilled in the back. Now I see where your question is coming from.

I'm going to take a leap of fate and assume there are no baffles in this overflow. Glass-Holes have baffles and the bulkhead hole pre-drilled. If no baffles, I believe you'd want to set this up as a ghost or Herbie. Sorry, I can't help you, but there are loads of DIY threads on installing these kinds of overflows.

Hey,

No this overflow doesn't have baffles, and it doesn't have the holes predrilled. the tank is already drilled though, so I just need to know how low from the top do I put the top of the overflow.