what size bulkhead is ideal?
 

i am looking to drill a few tanks, wondering what size bit to get also seeing what the best size of bulk head is thanks

I think 4 foot bulkheads are the best. that way you can get inside and really clean them :)

It all depends on what size the tank is and how much flow. The most common seem to be 1" 1 1/2" and 2 ".

ya thats what i was thinking, i was thinking on getting either a 60mm bit or a 65 mm bit

My tank has a 3/4" return, and a 1" overflow. The holes for those are 1 1/2" and 1 3/4".

Try this!

lol i dunno how much gph i am wanting i am just setting up a few tanks connected to one sump so i am drilling a bunch