180 Gallon Overflow

[colinm822]

What size bulkheads should I put on my 180 Gallon? And when I drill do I drill that exact size or just a smidge larger?

 

[Riblet]

2ea 1.5" drains
Take the BH and match it up with the hole saw that fits around it the tightest,it should just clear the threads.

 

[F-Dawg]

For a 180GA, I would go with 2x 1 1/2" drains. I like redundancy in my system just in case one gets clogged.
A 1 1/2" ABS bulkhead is 59mm/2.32". So you would use a 60mm Diamond coated bit if your drilling glass.
A 1 1/2" SCH.80 bulkhead is 64mm/2.51" So you would use a 65mm Diamond coated bit if your drilling glass.

 

[Riblet]

Make sure you check the actual bulkhead, because the size may vary between different manufactures of bulkheads.

 

[colinm822]

Use the same size for returns as well?

 

[Riblet]

Use the same size for returns as well?

3/4" ...