Silcone on Bulkheads?

[joshuasamuels]

Should I put any aquarium silicone on the glass before installing the bulkheads?

 

[AZDesertRat]

No. They should seal all by themselves. Hand tighten only with dry gaskets and keep the gasket on the flange or non nut sde.

 

[bingoreefer42]

But, as Anthony Calfo recommends, siliconing bulkhead threads before tightening the flange helps prevent small leaks, especially long term ones caused by the flange 'creeping' loose. I've also fixed leaks where the bulkhead went through a hole that was perhaps drilled a little too large, by using liberal amounts of silicon on the threads right where the flange tightens up against the tank wall. Of course, this was done on a small 5-gallon tank, and I would not recommend any kind of bulkhead leak fixing on larger tanks using silicon, especially if the bulkheads are low in the tank (and under more pressure.)

 

[pjf]

Silicone Lubricant?

Silicone Lubricant?

Here is silicone lubricant from Rainbow Lifegard:
http://www.drsfostersmith.com/Produ...ll&Ntx=mode+matchallpartial&Np=1&N=2004&Nty=1

I've got a bottle at home but have never used it. Is there any downside to using this on bulkheads?

 

[AZDesertRat]

Yes, it makes the gaskets slick and they want to squeeze out. Using silicone on a bulkhead is a crutch to make up for a poorly drilled hole or incorrectly sized hole. Silicone or any other sealant/lubricant is never needed on a properly fitting bulkhead.

 

[bingoreefer42]

Agreed, but locking the flange on with a non-permanent sealant such as silicone, helps prevent it from creeping loose over the years, similar to that lock-tite stuff you can put on nuts and bolts. Maybe this too is not that necessary, but I seem to have this creeping flange problem with bulkheads that feed large vibrating pumps.

Like I mentioned, I'd only use it as a leak-sealant crutch for this exact reason (too large of a hole), and only on very small tanks, and only on the threads, not the gaskets.

 

[AZDesertRat]

I can see where a vibrating pump could be an issue. I connect all my pumps with a short piece of oversized reinforced clear tubing myself so I don't get any vibration or noise treansmission through the remaining piping. This also acts as a strain relief so there is no uneven load or weight hanging on the bulkheads to stress them and make them leak. Been working good for over three years now on the present system with 5 bulkheads installed that way.

 

[hebdo27]

I sealed my BHs with Silicon...so good so far...8 mths. I guess it doesn't hurt with the added safety.