Different sized overflow holes

[Ross B Reef'n]

Are you sure it's 2" and 2 ¹/²" and not 1" and 1.5"? The bulkheads in the pic look too small to be that big. Of course the tank might just be that big that it's making the bulkheads look small.

I think you might be referencing the pic homer posted, the overflow tower is 14 inches long, 6 inches wide, and ~23 inches tall.

 

[Aquavaj]

I think you might be referencing the pic homer posted, the overflow tower is 14 inches long, 6 inches wide, and ~23 inches tall.

No I was referring to the cube tank pic. Im sure you already know this but the holes will be larger than the stated size of the bulkhead. A 1" bulkhead will have a hole close to 1 3/4". A 2 1/2" bulkhead will probably require a 3.5"-3.75" hole.

 

[Ross B Reef'n]

No I was referring to the cube tank pic. Im sure you already know this but the holes will be larger than the stated size of the bulkhead. A 1" bulkhead will have a hole close to 1 3/4". A 2 1/2" bulkhead will probably require a 3.5"-3.75" hole.

Ahh, I follow! I haven't actually got a caliper out and measured the bulkheads yet. My only reference was the build sheet left behind by the tank builders. I'll have to measure the bulk heads when I get home

 

[Aquavaj]

Yea a 2" hole will work for a 1-1.25" bulkhead and a 2.5" hole for a 1.5" bulkhead.

 

[ca1ore]

Depends if you are talking about the diameter of the holes or the nominal pipe size of the bulkhead. Glasscages typically uses Schedule80 bulkheads, so a 2 1/2" hole will take a 1 1/2" bulkhead. A 2" hole takes a 1" Sch80 bulkhead. You could use all three holes for a bean-style overflow or one of them for the return. Either way, use the largest as the emergency.

 

[Ross B Reef'n]

Survey says:

The center hole bulkhead fits 1-1/2" PVC pipe, the outside hole bulkheads fit 1" PVC pipe.

 

[ca1ore]

Yes, and those are sch80 bulkheads. T’were my tank, I’d use all three for drains and find an alternative route for the return.

 

[Ross B Reef'n]

Yes, and those are sch80 bulkheads. T’were my tank, I’d use all three for drains and find an alternative route for the return.

The tank is in a wall, so I'm going to do a bean animal and run the returns up the sides.

My build thread is here:
https://www.reef2reef.com/threads/ross-b-reefn-170-gallon.591540/