What kind of sealant ? I have some fish tank silcone here but they say not to use it because it makes the rubber seal move....techen said:Inside of the tank, I'd get some sealant for it cause I had leaks from things like those too. It's mostly down to being cheaply made and too much pressure.
I so wish i thought of putting the nut on the out side before i spent all day putting it on the inside. I have a overflow in my tank and have 2 holes at the bottom of the overflow for inlet and outlet and i had to try and get ym arm down in the overflow to screw the nut on well another person held the threaded bit. Will the silcone around the bulkhead damage the seals ? Has you can see from the pic i have a black rubber seal and then a plastic seal. I have put the 2 bulkheads in with the nut on the inside and there is a little drip ( not much ) so i sicloned around the bulkhead to try and stop the drip. But i have been looking around google and have read that the silcone will buy the rubber seal...DrRob said:Personally, I remove the rubber ring, and put the nut on the outside, then use silicone instead of the rubber.
The pressure of the water holds the bulkhead against the tank.