Silicone Overview

[Rivermud76]

Silicone Overview

Silicone has long been one of those things in this hobby that has a billion myths. I've heard everything from "Only use the Aquarium Safe silicone you can buy at the fish store, the other stuff is toxic and will kill your fish." to "Silicon II has stuff that will get into your tank." I am here to debunk these myths.

Most silicone is quite safe enough to use for an aquarium. There are however certain things to avoid. Never use a silicone listed for Bath and Tile or one Listed for Kitchens as these contain Mildewicides and Fungicides, both of which are harmful to tropical fish. Silicone with labels such as Mildew Resistant or Anti-Fungal should be avoided at all costs.

GE Silicone 1

Silicone I contains Acetoxy Silanes which, during the curing process releases Acetic acid. This is a serious inhalation risk. Prolonged exposure may cause death. Of course this would require you sitting your head in a box full of silicone and breathing... hey wait, that's exactly what you are doing so be careful and make sure the room is well ventilated. Take breaks and go get fresh air. If you notice any nose, eye, or throat irritation get some fresh air soon.

Silicone should fully cure in 48 hours and the smell will go away leaving the silicon safe and non toxic. Silicone I is considered a very good glass bonding agent.

GE Silicone II

GE Silicone II cures a little bit differently. During the curing process it releases ammonia. This is a little less harmful than acetic acid. However it still will bother the respiratory system. Also, be careful with cleaning agents while it is curing because bleach and ammonia combine to form several deadly toxins. Silicone II does not bond as well to glass but is more than strong enough for the job of sealing an aquarium. Some versions of Silicone II will state “Not for Aquariums” or something similar on the tube, be sure not to use these products if you see that label.

Some other known good products:

DAP 100% Silicon #43112
Dow Corning 732 RTV Sealant
All Glass 100% Silicone
RTV108 from GE
IS808 from GE
NAPA Silicone
99AS CRL Clear Aquarium Silicone Sealant


Hopefully this will help clear things up for the DIY’ers here. One thing I would like to add is that the colored silicone in general is okay to use. I would recommend however that if you choose not to use clear silicone you read the MSDS sheet and check to see if it is waterproof and will not leech due to the fact that certain coloring elements might be toxic and not all companies use the same coloring compounds.

 

[Lateral Line]

Many "own brand" silicone sealants neither state what type they are or whether they contain fungicides. Indeed, there are named brands which are simply badged versions of other brands, and they come from different sources depending on the raw material prices, i.e. you cannot tell what is in them, and even if you analyse the stuff today, the next batch may be different.

Anyone is free to use whatever silicone sealant they choose, I would never use anything that did not specifically say "For Aquarium Use". The differences in the curing process between the two is not really an issue, it is the additives.

 

[Rivermud76]

What addatives exactly are you speaking of? I thought that was pretty clear, listed the correct brands of silicone to use and what to avoid.

I figure you probably should see what GE has to say about it. The link is to a thread that details questions asked of GE and their replies.

Safe Silicone

As for the curing process, thats more for a health issue than anything else. It was meant to be educational.

 

[Lateral Line]

As is often the case with Americans, you list products and make statements that may well be true in the US.

You cannot be certain what is in "Silvan" silicone sealant. "Silvan" is a DIY chain in Denmark. They sell silicone sealants under their own brand name. As I said in my post above, this is not made by them, it is badged. Which batch was made by which manufacturer and to what specification changes with the price of the raw material.

Your comments about fungicides and mildew resistant are perfectly true, but many cheap suppliers would not think hard enough to even mention that.

My advice is not a generalisation, if it says on the tube it is safe for aquarium use, then it probably is. If it does not say that, then it MAY be okay. I do not suggest you should only buy the stuff the LFS sells, I buy silicone sealant in Silvan, but I use the named products which specifically say it is suitable.

 

[abstract]

As is often the case with Americans, you list products and make statements that may well be true in the US.

You cannot be certain what is in "Silvan" silicone sealant. "Silvan" is a DIY chain in Denmark. They sell silicone sealants under their own brand name. As I said in my post above, this is not made by them, it is badged. Which batch was made by which manufacturer and to what specification changes with the price of the raw material.

Your comments about fungicides and mildew resistant are perfectly true, but many cheap suppliers would not think hard enough to even mention that.

My advice is not a generalisation, if it says on the tube it is safe for aquarium use, then it probably is. If it does not say that, then it MAY be okay. I do not suggest you should only buy the stuff the LFS sells, I buy silicone sealant in Silvan, but I use the named products which specifically say it is suitable.

[snapback]869381[/snapback]​

he never claimed it was an exhaustive international list of acceptable silicone products to use....he simply stated what he knew about GE products (and a couple others)...i don't see why it has caused problems?

as is often the case with you international folks, you blame us for talking about the products in our country and not yours (just kidding just kidding! )

 

[Lateral Line]

>>> don't see why it has caused problems?

Problems, what problems?

He has passed on some information which may well be of use to members in the US. He did, however, make a few generalisations which are just that, generalisations. I highlighted some of the issues he did not address in his post.

In particular, in very many countries around the world...

>>> Most silicone is quite safe enough to use for an aquarium.

... is the opposite of the truth.

 

[Rivermud76]

I honestly don't know whether to take offense to that remark or not. "You Americans,"; what exactly about me being American makes the information posted any less useful or informative? I think Abstract stated it as correctly as I could, I simply posted the information known about specific products.

Let's speak of facts regarding silicone.

Addatives:
One additive in silicone sealants is fungistat, which resists mildew. Other additives include iron oxide for stability at higher temperatures, platinum to retard flames, and others to increase shelf life.

Not all products contain these addatives. Clear Silicone would not contain the heavy metals. Clear silicone without fungistat would then be safe for aquariums. RTV108 and IS808 both are sold to 3rd party vendors and both are aquarium safe if not treated with fungistat.

SIMPLE. Honestly if you need the information on the product in question from a 3rd party vendor/packager just ask them who the supplier is and which product they use. All Glass Brand silicone is actually GE RTV108 with an All Glass label. If you think that each batch is going to be distinctly different based on product availabilit I fear you are sorely mistaken. If a product is marketed under a 3rd party brand name then it must have an MSDS attached to it as well. I am sure europe keeps even tighter regulations that the US in this regard as they do in nearly every other instance. That means they would have to modify the MSDS which would require a government regulating body to review before it could be marketed. Yeah, a batch might be different in that it has .05% more Silicon Filler versus the last batch but they can't just randomly change active ingredients that make up the chemical curing and longetivity of the product.

 

[Lateral Line]

>>> makes the information posted any less useful or informative?

Err, I just said...

>>> He has passed on some information which may well be of use to members in the US.

However, let's speak of facts regarding silicone.

>>> If a product is marketed under a 3rd party brand name then it must have an MSDS attached to it as well.

:sigh:

>>> I am sure europe keeps even tighter regulations that the US

Most of the world is not Europe and North America.

>>> If you think that each batch is going to be distinctly different based on product availabilit I fear you are sorely mistaken.

Having worked in the chemical industry for a while, I can absolutely guarantee that "own brand", (etc.), products like sealants are bought in batch lots by the buyers, (more usually the buyers agents), on the spot market from around the world. The standards of production in some of the developing world are poor, and the regulation, inadequate and open to corruption.

By the time a Ukrainian agent has purchased a batch of sealant from a plant in Nigeria and shipped it to Indonesia for packaging prior to selling it in a discount chain in Brazil - the chances of finding out from anyone what is actually in that tube is zero.

The point I made before, is that even if you had it analysed and found it to be fine, a week later, the same "make" of sealant may contain a Philippine product bought by an Indian and sent for packaging in Argentina before arriving at the same store.

If a product is from a manufacturer rather then a badged version, and the tube is marked, "suitable for aquarium use", then it will be fine. The majority of sealants available around the world do not fall into that category however, so "most silicone is safe" is not the case.

You are quite free to disagree with me. I, of course, can also disagree with people.

 

[andywg]

I'm with Lateral on this one. I have quite often looked at silicone tubes in DIY chains in the UK and there is no informationa bout the contents at all.

And no need to become defensive about the "you Americans" especially as that phrasing was never used . It simply points out that so often on this board people from the Northern New World forget how different the rest of the world can be with regards to products and information on them.

I have no doubt that the information you have prevented is spot on. However I have never seen GE for sale over here and outside of lfs have never seen a sealant that I can put my hand on my heart and say "this will be fine".

 

[Dorkhedeos]

americans? isnt denmark in america?

 

[andywg]

americans? isnt denmark in america?

[snapback]869784[/snapback]​

 

[Lateral Line]

Actually, one of the quays in the main port at Copenhagen is called "Amerika Kaj" - America Quay. Thus, America, is simply a quay in Copenhagen.

 

[Waterloo Kid]

americans? isnt denmark in america?

Nah,, Denmark is near London, just like the entire of the UK. Oh and the UK consists of, errr, well, England.
Wales? They be big fish right?

Before I get jumped on for being anti American I'd like to point out that I could probably name only 10-20 states of the USA (at a push). In fact I'd probably not be able to name all the countries in Europe! Now I feel stupid!

WK

 

[andywg]

There's only one European country you need to know the name of...England. The rest don't matter.

 

[StrontiumDog]

I'm going off topic here but, MSDS mean nothing unless it contains all the CAS numbers of all the products/chemicals used in the end product. To me if they don't have the CAS numbers on the MSDS it means OX POOH. If someone knew what the're handling ....................they would touch the stuff. So no one would buy it.

On topic: I would buy only silicone rated for aqarium use myself , but with more factories moving to 3rd world countries for these products, for the purpose of cheap labour. You have no real knowledge your getting what you're suposed to be buying. ( Ok that wasn't much on topic ) )