Issue with my new 150g plumbing.

[markw]

Hi all. I am setting up a 150g reef tank. It has dual overflows in the corners. I put about an inch's worth of water in the tank to test the seals on the bottom of the overflows. They were fine. So, I took the same water and put in one of the overflows. After I got about an inch or so in there, the bulkhead began to leak. The same bulkhead is wobbling when pushed on, so I know it's not tight enough. Just to be safe, I was going to replace it. The thing is, I cant seem to get the thing off. Can I use a wrench to do this?
Also, none of the other bulkheads are leaking, should I replace them since the tank is used, or should they be okay?
Mark

 

[scsinet]

Usually, once you tighten down a bulkhead it should remain leak free unless disturbed. Removing the plumbing from a tank during tear down qualifies as disturbing. Gaskets can degrade, so it's no surprise that one is leaking.
If it were me I'd replace all four to be safe, but at the very least I'd replace just the gasket on the one that's leaking. When installing new bulkheads, I like to spread a thin film of silicon on the gasket before tightening down. It makes the bulkhead leak-free every time, and without tightening down so hard I worry about the glass.
It sounds like the locknut on the bulkhead is jammed up with salt creep. It may have been leaking previously, causing this. You can use a wrench with care, just don't stress the glass very much.