silicone and bulkheads

TracyZeuner · 07/15/2006, 04:43 PM

Is it ok to use silicone on a bulkhead? The reason I ask is because I was just water testing my tank and the return bulkhead leaked. I already ordered another one from my LFS but dont want to go thru that again. Should I use some silicone just to be safe?

leoskee · 07/15/2006, 05:56 PM

I did on my sump. I had a tight seal from the start but I know I can sleep better at night knowing that the bulkhead is sealed with silicone from both sides.

If the bulk head is in a visable area I would seal the outside portion. x

And the best part is that if I want to remove it all it takes is a sharp blade.

AZDesertRat · 07/15/2006, 06:17 PM

If you have to use silicone to seal it something is wrong. You either have stress on it from the piping or fittings or it is either too tight or not tight enough. Silicone makes the gasket want to scoot out which leads to leaks. The best seal is with perfectly dry and clean surfaces when assembling. Make sure the flange is on the inside along with the gasket.

TracyZeuner · 07/15/2006, 07:04 PM

This may sound stupid, but what is the flange? The way I assembled mine was with the gasket on the wet side(the inside of the tank) and the part with the screws on it was facing down toward my sump. I do think I stresed the piping. I was using spa-flex and the bend was tight and I dont think I let the glue dry long enough. I think I will use hard pvc to connect to the pump next time

AZDesertRat · 07/15/2006, 07:43 PM

The flange is the larger end that does not have threads. The end opposite the flange is where the nut screws on. Unequal stress is a common cause of bulkheads leaking. Try not to support any weight with the bulkhead, brace or strap down any piping suspended from the bulkhead so you are not forcing it one direction or another.

TracyZeuner · 07/15/2006, 07:58 PM

That was my problem, I stressed the joint. Live and learn

LittleBlueGT · 07/15/2006, 11:53 PM

On my sump I use bulkheads as normal.

For my CL in my 250 I use sch80 bulkheads w/ no gasket. I then clean both the glass and bulkhead with isopropyl. Then you have to us the correct silicone to bond glass and piping. I use Dow corning 795. Let cure for 2 days.

My bulkheads can support 200 lbs of weight each. For my that is nice insurance, and helps me sleep knowing I won't have 250 gallons on the floor.

07/15/2006, 04:43 PM	#1
TracyZeuner Registered Member Join Date: Apr 2006 Location: Simi Valley, Ca Posts: 636	silicone and bulkheads Is it ok to use silicone on a bulkhead? The reason I ask is because I was just water testing my tank and the return bulkhead leaked. I already ordered another one from my LFS but dont want to go thru that again. Should I use some silicone just to be safe?

07/15/2006, 05:56 PM	#2
leoskee Registered Member Join Date: Dec 2004 Location: NJ/NY Posts: 371	I did on my sump. I had a tight seal from the start but I know I can sleep better at night knowing that the bulkhead is sealed with silicone from both sides. If the bulk head is in a visable area I would seal the outside portion. x And the best part is that if I want to remove it all it takes is a sharp blade. __________________ ~Little Fish in a Big Pond~

07/15/2006, 11:53 PM	#7
LittleBlueGT Registered Member Join Date: Dec 2003 Location: Winnipeg, Canada Posts: 1,955	On my sump I use bulkheads as normal. For my CL in my 250 I use sch80 bulkheads w/ no gasket. I then clean both the glass and bulkhead with isopropyl. Then you have to us the correct silicone to bond glass and piping. I use Dow corning 795. Let cure for 2 days. My bulkheads can support 200 lbs of weight each. For my that is nice insurance, and helps me sleep knowing I won't have 250 gallons on the floor. __________________ When all else fails, turn up the flow!!! Current Tank Info: 250 starphire, 169 g sump in basement, 3 x ROIII on moving light rail, 4 icecap powered T5s, 2 URI VHO actinics, 55 X turnover with 2 OM units, zoos, clams, SPS

07/15/2006, 06:17 PM	#3
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	If you have to use silicone to seal it something is wrong. You either have stress on it from the piping or fittings or it is either too tight or not tight enough. Silicone makes the gasket want to scoot out which leads to leaks. The best seal is with perfectly dry and clean surfaces when assembling. Make sure the flange is on the inside along with the gasket.

07/15/2006, 07:04 PM	#4
TracyZeuner Registered Member Join Date: Apr 2006 Location: Simi Valley, Ca Posts: 636	This may sound stupid, but what is the flange? The way I assembled mine was with the gasket on the wet side(the inside of the tank) and the part with the screws on it was facing down toward my sump. I do think I stresed the piping. I was using spa-flex and the bend was tight and I dont think I let the glue dry long enough. I think I will use hard pvc to connect to the pump next time

07/15/2006, 07:43 PM	#5
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	The flange is the larger end that does not have threads. The end opposite the flange is where the nut screws on. Unequal stress is a common cause of bulkheads leaking. Try not to support any weight with the bulkhead, brace or strap down any piping suspended from the bulkhead so you are not forcing it one direction or another.

07/15/2006, 07:58 PM	#6
TracyZeuner Registered Member Join Date: Apr 2006 Location: Simi Valley, Ca Posts: 636	That was my problem, I stressed the joint. Live and learn