silicone bulkheads?

[demonclownfish]

ok so my dad thinks the bulkheads wont seal around the threads on my bulkheads and think they need to be siliconed as well. your opinions? this is one of the last peices to get my tank up so im anxious lol

[BK's Reef]

use teflon tape on the thread. if you are talking about the part against the glass you can silicone it but it usually never leaks

[demonclownfish]

thanks, and does the rubber gasket go above the hole or under the hole?

[BK's Reef]

sorry i dont know what your talking about

[demonclownfish]

the flat rubber disk with the hole in the middle

[BK's Reef]

put it on the outside of the tank with the bulkhead holding it firm

[tankdude]

The gasket goes on the wet side, or the side with the water. I used silicone on my bulkheads, none of them leak.

[demonclownfish]

The gasket goes on the wet side, or the side with the water. I used silicone on my bulkheads, none of them leak.

where did u silicone them? between the plastic and ghasket? or after the gasket? or after you put the bulkhead on and just went around the outside?

[tankdude]

I put some on the thread side, that way when I tighten it it smushes out, I have put it on both sides before, it works either way. I guess you don't really have to use any silicone, I did it just because I'm paranoid about leaks.

[Wy Renegade]

Mine have never leaked either, and I've never put silicon on any of them ;)

[cephalotus]

Do not ever put silicone on bulkheads they are designed to seal directly to glass. After time the silicone will fail and cause a leak. And yes you need to put the gasket on the wetside and do not overtighten.

[tankdude]

Do not ever put silicone on bulkheads they are designed to seal directly to glass. After time the silicone will fail and cause a leak. And yes you need to put the gasket on the wetside and do not overtighten.

I still don't trust them. I'm going to do what I think will keep water off my living room floor, if that means a little dab of silicone thats what I'm going to do.

[AZDesertRat]

Follow these tips from a sticky thread I did for several forums:


Installing Bulkhead Tips
Bulkhead tips:

1. Always install bulkheads clean and dry, no silicone, teflon or thread lubricants. Silicone and lubricants cause the gasket to scoot out or not seal properly. Have you ever removed an old automobile windshield or other gasketed glass? The rubber vulcanizes to the glass with time and creates a perfect seal without any help.

2. Before installing the bulkhead take a few minutes using a jewelers file, nail file or pocket knife and clean any excess flashing off both the male and female threads and from the flat gasket mating surfaces of the flange and nut. This is a common source of leaks.

3. Always install the gasket on the flange side of the bulkhead, never on the nut side, regardless if its inside or outside the tank. Installing the gasket next to the nut will lead to leaks as water travels along the threads around the gasket. Hand tighten only with maybe 1/4 to 1/2 turn additional, no more.

4. When using threaded bulkheads, again clean the excess flashing from the threads and valleys and use a small amount of teflon tape or better yet the stick or crayon type of thread lubricant designed specifically for PVC treads. These can be found at Lowes, HD, Ace and all hardware stores under names like Laco, Permatex and others.

I use this one and have since the 1980's with great success.
LA-CO: Product Detail - PLASTO-JOINT STIK
It stays pliable forever and does not tear or roll out of the threads like teflon tape. My swimming pool plumbing up to 2" was all installed with this in 1983, outside in Phoenix AZ and its still pliable to this day!

5. Never support any pumps or piping from a bulkhead, always use supports so weight is not on a bulkhead and gasket causing differential stresses on the mating surfaces and leaks.

6. Never screw anything to the external threads of a bulkhead, these are not standard tapered pipe threads (NPT) and will leak. They are there to screw the nut on is all and are not normally even a standard diameter like 1" etc.

Hope you get some use out of this.

Here is a link to the whole thread on one of the forums:
http://www.reef2reef.com/forums/equipment-lighting-hardware-diy-discussion/34973-installing-bulkhead-tips.html