Need input on overflow hole size

[StirCrazy]

Ken, I strongly recommend that you buy the actual bulkheads you are going to use first then take the size you need directly off them. I made the mistake of listening to people who said "all bulkheads are standard size" well they are not.

I bought 1.5" bulkheads from a plumbing supply and the hole they use is bigger than the one Seastar uses.

I got lucky as I had my tank made with the holes so Seastar threw in the bulkheads I needed and I was able to return the ones I had bought...

If I would have had a local glass shop cut the holes I would have been running around trying to find the right ones.

Steve