RTV liquid gasket for overflow bulkheads?

[pygo1]

So, I just bought a secondhand tank and am in the process of leak testing. The tank seals are ever so slightly worn, but it holds water just fine. However, the overflow box had a slow drip overnight and I could see it was coming from the bulkheads. I loosened them up and found that there are no gaskets installed. Just plastic on glass. I have no clue how this guy was able to run the tank like this lol. I tried to remove the whole thing, but I’m pretty sure the union below it is glued on, so I’ll likely have to cut it and replace everything, UNLESS, I can use one of those liquid gasket products and seal around it. Once installed, I have no plans of replacing/removing pipe, so I can go really overkill on the sealant if required.

But, I’ll see what kind of bulkheads and other fittings I have available at work before I go that route. Just wondering if it’s an option

 

[Crabs McJones]

Aquarium grade silicone would be the only one I can think of that would work long term with no chance of leaching chemicals into the water

 

[pygo1]

Aquarium grade silicone would be the only one I can think of that would work long term with no chance of leaching chemicals into the water

I got some gasket rubber from work, so im going to cut out some gaskets and try fitting them on. Im hoping the Threads were just stuck on that union and that it’s not actually glued, but I’ll find out in a bit when I get home.

As for the silicone, it seems like quite a few people say not to do it. But then again plenty of people also say go for it lol

 

[GSPClown94]

In your second picture I would expect the gasket to be on the flange side of the bulkhead, double check to make sure there is one there? I'd personally just clean the gaskets and tighten them down then check for leaks.

 

[Troylee]

Gasket should only be on the wet side.. make sure it’s clean and it will seal.