Is your Drilled Bulkhead Hole too Big?

[SteveMM62Reef]

The Bulkhead holes on the back of the tank were a little larger than the One Inch Bulkheads. OD Someone used Silicone on it to fix, which I didn’t want. Went to an Ace Hardware, picked up Two #99 1-1/2” x 1-3/4” x 1/8” “O” Rings. Slipped them over the outer threads. They Take up the gap perfectly. On Amazon they are listed as a #222 “O” Ring. I never understood the “O” Ring Numbering!

 

[blaxsun]

And problem solved!

 

[bigjonbird]

Thanks for posting this. I was thinking of doing the same thing. My holes are about 2mm too big. They are probably fine but I wanted to add a little extra material to make sure it seals.

 

[UncommonSense]

Assuming the bulkheads fittings being used already aren’t schedule 80, it’s possible that some of these holes are oversized for thicker sch.80 bulkheads!

For example, Hayward BFAS series bulkhead fittings in 1” call for a 1-7/8” minimum hole size (and that really is friction-fit minimum, going out to 50mm would be preferable), vs. 1-3/4” hole size for a typical sch.40 bulkhead!

 

[SteveMM62Reef]

I had an Aquarium like that. As long as the fitting was centered, no leaks. I purchased an “O” Ring from the Hardware Store, to keep the Bulkhead Fitting Centered. The “O” was not make the Fitting water tight, the Gasket was.

 

[bigjonbird]

I had an Aquarium like that. As long as the fitting was centered, no leaks. I purchased an “O” Ring from the Hardware Store, to keep the Bulkhead Fitting Centered. The “O” was not make the Fitting water tight, the Gasket was.

That is exactly what I was thinking, getting it centered will be the best thing I can do. Thanks!