Silicone for 200g tank? Momentive vs GE

nanomania · Sep 2, 2016

Hey guys, im planning on a 200g build, iv never used black silicone, but im planning to use black silicone. However i read alot and im still confused as what works best.

Id like to know if someone has used momentive rtv 103/108 on their 200g or 200+g tank. Also have heard about ge scs 1200, many claim its strongest silicone in the market.

Iv always used clear silicone, but later it tends to have algae penetrating in it. Many use black silicone to prevent this issue and iv also heard it increases the longitivity of the aquarium.

Im asking this coz this will be my largest build ever and might not go for a bigger tank for atleast 15years or more. So want something that could work for that long.

nanomania · Sep 3, 2016

Please help guys..

cromag27 · Sep 3, 2016

I used to build glass tanks and I only used momentive 100 series.

nanomania · Sep 4, 2016

cromag08 said:
I used to build glass tanks and I only used momentive 100 series.

Rtv 103 black, how long should i keep it dry for curing?

cromag27 · Sep 4, 2016

One full week. of you still smell ammonia, give it another full week.

nanomania · Sep 4, 2016

cromag08 said:
One full week. of you still smell ammonia, give it another full week.

Can i go rimless? 12mm glass 6x2x2 feet..

TylerS · Sep 4, 2016

I'd compare to commercial rimless tanks of that size to see if you can go rimless. For silicon you could always buy both and do some testing, or try to find published shear and peal strength, but that's probably not available.

mfinn · Sep 4, 2016

I made a small tank ( 30" x 20" x 20" ) with the momentive 103 black.
First thing I noticed about the momentive product, is you have alot less working time compared to a regular silicone.
I did it by myself and I wish I had called a friend to help, even with this small of a tank.
With a large one like you are planning I would add atleast one more set of hands plus the crew you already have in mind.

nanomania · Sep 4, 2016

TylerS said:
I'd compare to commercial rimless tanks of that size to see if you can go rimless. For silicon you could always buy both and do some testing, or try to find published shear and peal strength, but that's probably not available.

Both means? 103 and 108?

nanomania · Sep 4, 2016

mfinn said:
I made a small tank ( 30" x 20" x 20" ) with the momentive 103 black.
First thing I noticed about the momentive product, is you have alot less working time compared to a regular silicone.
I did it by myself and I wish I had called a friend to help, even with this small of a tank.
With a large one like you are planning I would add atleast one more set of hands plus the crew you already have in mind.

Im gona hire professionals to do it, just that they have never worked with black silicone before, and have used ge only.

cromag27 · Sep 4, 2016

No.

nanomania said:
Can i go rimless? 12mm glass 6x2x2 feet..

cromag27 · Sep 4, 2016

They aren't professionals then. GE is garbage and silicone being black is irrelevant.

nanomania said:
Im gona hire professionals to do it, just that they have never worked with black silicone before, and have used ge only.

nanomania · Sep 4, 2016

cromag08 said:
They aren't professionals then. GE is garbage and silicone being black is irrelevant.

Well they are the oldest at building tanks and use ge i guess. Even for my current tank 3yrs old 54x24x24" they used it. Its fw planted. But this time im plannin on black as i want it to last like forever. So ill add braces at the bottom and top then. Howmany tubes i will require? Any idea? As i have to call for it.

cromag27 · Sep 4, 2016

It's your tank, your flood.

cromag27 · Sep 4, 2016

Sorry had to restart my phone. r2r is not mobile friendly. anyhow.....

I was obviously be facetious but with a purpose. extra bracing may not help cheap household silicone bond any better. momentive is industrial strength and that is why myself and several of the largest glass tank manufacturers use it. If they guys know what they're doing, they'll know how to use is appropriately.

If these guys gave you a deer-in-the-headlights look when you mentioned momentive, then I would highly suggest finding someone else.

cromag27 · Sep 4, 2016

You might want 4 or 5 tubes.

TylerS · Sep 4, 2016

nanomania said:
Both means? 103 and 108?

I didn't realize you're trying to find recommendations for silicon that a tank manufacturer will be using? They should have experience with a particular product, and know from their experience if it will work or not. If they don't use or have experience with the products you prefer for one reason or another I would find someone who does.

Just FYI, I've never looked into silicone seriously before, but here's the data sheet for the momentive 100 series. http://www.momentive.com/products/showtechnicaldatasheet.aspx?id=10289

What's the GE series that you're looking at?

TylerS · Sep 4, 2016

I missed that you said the specific GE product in the 1st post.

http://www.siliconeforbuilding.com/pdf/speciality/Data_Sheet_SCS1200_Construction.pdf

The GE product you mention is slightly stronger than the momentive.
Tensile strength GE is 480PSI, momentive = 400PSI
Elongation for the GE is 513%, momentive = 450%
Shear strengths may not be comparable - GE = 111PSI, momentive = 200. GE specifies a 1/4" thickness, the momentive does not specify the thickness used for testing. 1/4 is obviously way thicker than would actually be used on an aquarium seam. Typically a material with a stronger tensile strength also has a stronger shear strength.

They're really not that different. I think the seams are loaded differently (tensile or shear) depending on the location on the tank and the configuration of the panels at the joints.

cromag27 · Sep 4, 2016

Scs1200 is for construction purposes and it is a glaze. Shouldn't be used underwater. NOT the same thing as momentive 100 series.

TylerS · Sep 4, 2016

cromag08 said:
Scs1200 is for construction purposes and it is a glaze. Shouldn't be used underwater. NOT the same thing as momentive 100 series.

Just because you've used momentive in the past doesn't mean it's the only product that will work. And it doesn't look like we're comparing momentive 100 series to home depot stuff.

I've posted links to data sheets, feel free to take a look at them. Here's what I can find on the SCS1200 data sheet regarding marine and underwater application in a quick scan. "SCS1200 Construction silicone glazing sealant is a one-component, high strength, acetoxy silicone adhesive for structural, butt joint and general purpose glazing applications."
"SCS1200 may be considered for sealing air conditioning, vents or other wall penetrations; glass block, metal/plastic signs or marine hardware." Also under the limitations section: "Contact Momentive technical services for applications where sealant is used underwater or in continuous contact with water."

I think if the OP want's to look further into this GE product there's no reason he shouldn't from what I can see on the spec sheet. It looks like "glazing" sealant means for use sealing glass windows. So it's a product that's designed for high strength structural, butt joint and general purpose glazing of glass... which is about as similar as it gets to aquarium use. The momentive product doesn't specifically mention it can be used underwater for aquarium building from what I can tell. From the spec sheets I don't see a reason to pick one over the other, except the GE product is stronger and has higher elongation until fracture. I didn't get into working time or anything like that in my quick scans, but if the OP is seriously considering specing the sealant used then he needs to, or not spec it at all and go with what his builders use.

If it was me I would talk to the builder about it and see what they typically use and what their warranty is, and I would contact momentive before using either product for aquarium building (which it seems like that's covered for the 100 series since that's what you used to use). Or just contact momentive and see which product they recommend (since it's the same company...).