Silicone bulkheads or no?

Vapour1ze · 09/14/2014, 12:20 PM

I've seen 50% of people say yes, and the other 50% say no.

I have a tube of RTV 108 that I'll be using for my baffles, I was going to apply a small amount to the threaded side of the bulkhead. Yay or nah? My last build I did and didn't have any problems. However, the more I read now, the more I hear that it actually can cause a leak down the road. So should I just try it without silicone and see what happens?

Thanks

PL-Reef · 09/14/2014, 12:54 PM

No. A properly installed bulkhead does not need any silicone.

billsreef · 09/14/2014, 12:55 PM

No silicone needed or required. Just clean surfaces

ca1ore · 09/14/2014, 01:46 PM

Using silicone on a bulkhead will not cause it to leak down the road, but assuming it is done correctly, it makes removing the bulkhead a real chore. For most bulkhead installations it is not necessary. As others have noted, clean surfaces and the gasket on the flange side is all that should be needed. The only time I uses silicone on a bulkhead is if it's situated in a place where having to reseat it would be inconvenient. The dozen or so that I have installed this way have all lasted for a a long as I needed them to last (in one case, 19 years).

icebrg5 · 09/14/2014, 01:53 PM

The bulkhead on my tank originally never had silicone on it but i then upgraded to an internal overflow box and when i replaced the bulkhead i could never get it to stop leaking no matter what i did so in the end i did put a very thin bead of silicone around the bulkhead and its held every since.

Not saying that you should use it but there are some situations where you might have no other choice. In my situation it was my last option as the outside surface area of the tank was not smooth at all and the inside of the overflow box was such a tight space i couldn't get my hand into it i saw that i had no other choice but to use silicon.My tank is acrylic and has a top as well and the overflow is in the middle of the tank about 2 from the top so the top cover blocks my access to the inside of the overflow.

Vapour1ze · 09/14/2014, 03:07 PM

Thanks! I'll try it without and watch it, if I get any leaks I'll put a slight bead around the edge.

billsreef · 09/14/2014, 03:55 PM

Quote:

Originally Posted by Vapour1ze

Thanks! I'll try it without and watch it, if I get any leaks I'll put a slight bead around the edge.

If you get any leaks, drain, dry, clean, and do it over. Using silicone around the edge like that is only a band-aid approach...likely to be trouble down the line.

When you install the bulkhead, hand tight plus only 1/4 turn. Probably the most common mistake people make is over tightening

salty joe · 09/14/2014, 04:17 PM

In the case where you need silicone-I know, I know-lots and lots of people say you NEVER should use silicone on a bulkhead- but if you end up using it a method I've used for decades with great success is silicone the part, very lightly hand tighten and wait for a day or two for the silicone to completely cure before snugging it up. I've used that method on problem sink drains, problem oil pans, lots of stuff. Sometimes things are not perfect and the cost to make them perfect is high. Many times this method has given me a perfectly good, long lasting seal.

But generally I agree silicone is not needed for a typical aquarium bulkhead installation. In fact silicone can cause a leak by causing the gasket to slide out of position when it is tightened on uncured silicone.

+1 on what Bill said. A bead around the edge is a waste of time.

09/14/2014, 12:20 PM	#1
Vapour1ze I'm an Addict. Join Date: Mar 2008 Location: Yorkville, IL Posts: 3,036	Silicone bulkheads or no? I've seen 50% of people say yes, and the other 50% say no. I have a tube of RTV 108 that I'll be using for my baffles, I was going to apply a small amount to the threaded side of the bulkhead. Yay or nah? My last build I did and didn't have any problems. However, the more I read now, the more I hear that it actually can cause a leak down the road. So should I just try it without silicone and see what happens? Thanks __________________ 93 Reef \| 220 Reef \| Basement Fish Life Support Room \| Empty Savings Account

09/14/2014, 12:54 PM	#2
PL-Reef Awesome Member Join Date: Nov 2005 Location: Chaplin,Ct Posts: 4,345	No. A properly installed bulkhead does not need any silicone. __________________ Jas tested, mother disapproved. Current Tank Info: 2 gallon goldfish bowl with a happy 7" Naso tang and 2 small Beluga whales. Just added a baby dolphin, large Trigger, a herd of Sea Horses and just fragged my first Manatee. All fish safely hand caught using organic cyanide.

09/14/2014, 12:55 PM	#3
billsreef Moderator 10 & Over Club Join Date: Oct 1999 Location: Long Island, NY/North Miami Posts: 36,538	No silicone needed or required. Just clean surfaces __________________ Bill "LOL, well I have no brain apparently. " - dc (Debi) Current Tank Info: Far too many tanks according to my wife, LOL.

09/14/2014, 01:46 PM	#4
ca1ore Grizzled & Cynical Join Date: Apr 2006 Location: Stamford, CT Posts: 17,319	Using silicone on a bulkhead will not cause it to leak down the road, but assuming it is done correctly, it makes removing the bulkhead a real chore. For most bulkhead installations it is not necessary. As others have noted, clean surfaces and the gasket on the flange side is all that should be needed. The only time I uses silicone on a bulkhead is if it's situated in a place where having to reseat it would be inconvenient. The dozen or so that I have installed this way have all lasted for a a long as I needed them to last (in one case, 19 years). __________________ Simon Got back into the hobby ..... planned to keep it simple ..... yeah, right ..... clearly I need a new plan! Pet peeve: anemones host clowns; clowns do not host anemones! Current Tank Info: 450 Reef; 120 refugium; 60 Frag Tank, 30 Introduction tank; multiple QTs

09/14/2014, 01:53 PM	#5
icebrg5 Registered Member Join Date: Apr 2014 Posts: 168	The bulkhead on my tank originally never had silicone on it but i then upgraded to an internal overflow box and when i replaced the bulkhead i could never get it to stop leaking no matter what i did so in the end i did put a very thin bead of silicone around the bulkhead and its held every since. Not saying that you should use it but there are some situations where you might have no other choice. In my situation it was my last option as the outside surface area of the tank was not smooth at all and the inside of the overflow box was such a tight space i couldn't get my hand into it i saw that i had no other choice but to use silicon.My tank is acrylic and has a top as well and the overflow is in the middle of the tank about 2 from the top so the top cover blocks my access to the inside of the overflow. __________________ Using Tapatalk

09/14/2014, 03:07 PM	#6
Vapour1ze I'm an Addict. Join Date: Mar 2008 Location: Yorkville, IL Posts: 3,036	Thanks! I'll try it without and watch it, if I get any leaks I'll put a slight bead around the edge. __________________ 93 Reef \| 220 Reef \| Basement Fish Life Support Room \| Empty Savings Account

09/14/2014, 04:17 PM	#8
salty joe Registered Member Join Date: Oct 2002 Location: medina, ohio Posts: 2,419	In the case where you need silicone-I know, I know-lots and lots of people say you NEVER should use silicone on a bulkhead- but if you end up using it a method I've used for decades with great success is silicone the part, very lightly hand tighten and wait for a day or two for the silicone to completely cure before snugging it up. I've used that method on problem sink drains, problem oil pans, lots of stuff. Sometimes things are not perfect and the cost to make them perfect is high. Many times this method has given me a perfectly good, long lasting seal. But generally I agree silicone is not needed for a typical aquarium bulkhead installation. In fact silicone can cause a leak by causing the gasket to slide out of position when it is tightened on uncured silicone. +1 on what Bill said. A bead around the edge is a waste of time. __________________ Time to roll the dice.