External Durso Overflow Anatomy

Tigah

Would it be possible to replace the hole with a small gate valve? Would that make it more easily adjustible?

Tigah - Please look into making a diagram of a Hoffer Gurgle Buster (search RC to find it)

It is a complex overflow, but I have had good exprience with it and it also has a compact size good for rescricted spaces.

if i understood this correctly, the smaller the hole, the faster the water flows through?

correct. the hole size is VERY important. the smaller the hole, the more likely it will form a siphon instead of a normal gravity-driven flow thru. And when it forms a siphon, that's the max gph flowing thru the bulkhead/overflow (but it will be noisy and not as consistant as gravity-driven).

see my post here for more info on the hole size: http://www.nano-reef.com/forums/index.php?act=ST&f=3&t=67834&st=220#entry621661

stoney - I have never tried the gate valve idea, but I think it would be a bit excessive for the task at hand. But lmk if u try it and it works.