What silicone are yall using?

SnakeBlitz33 · Jan 18, 2015

I am fixin' to buy some silicone at Home Depot and all I've found is window and door silicone made by GE. I see GE silicone I and GE silicone II

When I look at the labels, they don't say anything about being mold and mildew resistant. I figure if it was, they would put it on the label. Think it is safe to use?

Should I buy the silicone I or the silicone II?

redfishbluefish · Jan 18, 2015

Plain old GE Silicone I.

hybridazn · Jan 18, 2015

SnakeBlitz33 · Jan 18, 2015

GE1 it is then.

Anyone's opinion different?

Why GE1 and not GE2?

redfishbluefish · Jan 18, 2015

GE II does have inhibitors in there.

SnakeBlitz33 · Jan 18, 2015

Ah!!!! Ok. Makes sense.

Is it possible to buy black silicone GE I? Would the black have inhibitors?

Fin · Jan 18, 2015

I use Momentive RTV 103 black (RTV 108 is clear). You won't find it at Lowe's or Home Depot. It can be obtained through Grainger's, if you have a local outlet. Or, Amazon has it.

http://www.amazon.com/dp/B004V40OF2/ref=biss_dp_t_asn

JOKER · Jan 18, 2015

Momentive also. Some good stuff

davescrews · Jan 18, 2015

Dow 795

Zacco · Jan 18, 2015

This is what my LFS use's on all their projects. Zoo Med Rubberized Silicone. Comes in clear and black.

SnakeBlitz33 · Jan 18, 2015

Thanks guys.

I'm not hurting for black silicone. I'll just use the regular GE silicone 1.

glassguy · Jan 18, 2015

Dow 999. Its an acid cure, better than GE. just depends what you using It for.
Dow 795 is a structural silicone needs 21 days to cure fully. Works great on holding glass to the side of building though.

glassguy · Jan 18, 2015

JOKER said:
Momentive also. Some good stuff

I have also heard this is used by Aquarium builders

JOKER · Jan 18, 2015

Yep that's why I use it. If thy trust it I do too. Don't trust any of the other stuff. Heard nightmare stories of other stuff especially the ge2. The mold inhibiter is bad for tank. I do know that no silicone company will tell you their silicone is for aquarium use even though the label reads the same.

Fin · Jan 18, 2015

If you have ever tried to cut apart a project put together with GE silicone and another one done with the Momentive RTV, you will know the difference. The Momentive is some tough stuff and it is hard to cut it apart. GE, not so much.

hybridazn · Jan 19, 2015

Fin said:
If you have ever tried to cut apart a project put together with GE silicone and another one done with the Momentive RTV, you will know the difference. The Momentive is some tough stuff and it is hard to cut it apart. GE, not so much.

True, which is why I always recommend using GE silicone on small tank builds (under 30 gallon) and baffles for sumps.

slowngreen · Jan 20, 2015

Be careful! Some ge1 will kill. I lost most of my coral after adding a new sump using ge2 but around the same time another guy I know used the red label ge1 and lost everything. Best way to know is to find the one you want on home depots website, if it has any mold killers They will say so in the specifications. With that said, the only ge silicone I've found recently that doesn't have a mold killer in it is the ge silicone for plastic which is sold with the acrylic sheets. All the ge1's list mold resistant in their specs now, at least the ones in stock at my local store.

SnakeBlitz33 · Jan 21, 2015

Wow. This thread has been very informative. I guess I'll order the right stuff online then and have it shipped to me. I think the last tank I had crashed because of bad silicone and bad RO unit filters.

Thanks yall

redfishbluefish · Jan 21, 2015

OK, here's the bottom line on silicones. Some act more like a sealants while others act more like an adhesive. GE Silicone I is a better sealant than adhesive, while the RTV silicones are better adhesives than sealants. If you're installing baffles in a sump, I'd use a sealant type silicone. If I were building a tank, I'd use an RTV adhesive silicone. Hope that helps.

Regardless of the silicone used, you need to let it cure. I'm willing to bet the tank crashes from GE Silicone I was from the tank being put into service before the silicone cured. I like to let my tanks sit at least a week before I put a drop of water into them. You know it's not ready because it still stinks. That's my two cents.

SnakeBlitz33 · Jan 21, 2015

But just for installing a drain box on the back of a tank for a bean animal overflow, you would use an adhesive rather than a sealant? I guess I might as well use RTV then.