What kind of silicon is aquarium safe?

**reiner09** · 5th Nov 2011, 21:41

Hi, can anybody here recommend some brands of silicon that will be aquarium safe?
I got a bostik simson ISR 70-04 industrial silicon to seal the crack on my canister ,i don't know if it is aquarium safe hence i am asking.If it is not safe ,i will have to scrape it off soon.
I did some reseach and realise there are GE1 and GE2 and i do not know which GE my silicon belongs to. Can any experienced in DIY bros help to solve my problem?
Thanks in advance for the advise and recommendations.

**Shadow** · 5th Nov 2011, 22:01

you can buy the one sold at LFS

**reiner09** · 5th Nov 2011, 22:02

hmm..but i already applied it..if it is safe then i do not have to remove it..

**reiner09** · 5th Nov 2011, 22:09

it is a Silyl Modified Polymer base silicon.Is it safe for aquarium? it is the latest type of silicon available in the market.Usually used for car windscreens.

One of the newest sealant technologies

Enable broad use in construction, industrial, DIY, automotive, marine and transportation markets (not recommended for structural sealant glazing applications)

Excellent adhesion and movement capabilities; good UV and heat stability

Paintable

Provide exceptional bonding to plastics, metals, wood and stone

Can exceed ± 50% joint movement capability (ASTM C 920) even in low temperatures

Contain no solvent, contribute less VOC, and yield lower odors compared to other chemistries

AND

Bostik's SMP sealants & adhesives do not contain solvents and isocyanates and are free of odor. There are no harmful constituents added to the product or formed during reaction. Not only is this product user friendly and safe for employees, it also reduces the possibility of incompatibility with substrates as there is less stress corrosion and chemical attack.
The elastic adhesives and sealants based on SMP have been used meanwhile in several building, construction and industrial areas (transportation, assembly) and will be used more often in the forthcoming years because of their specific characteristics, especially in those places where traditional systems meet restrictions.

I don't know if this is conclusive enough to show that it might be safe?

**reiner09** · 6th Nov 2011, 22:40

I guess nobody has the answers to this..can anybody recommand shops that sells aquarium safe silicons that resides in the west ? Thanks in advance.

**stormhawk** · 7th Nov 2011, 03:39

I don't think this one is aquarium safe, however you can contact the local Bostik agent and ask:

Bostik Singapore Pte Ltd
10 Toh Guan Road #09-03
TT International Tradepark
608838 SINGAPORE
Tel: + 65 6863 4088
Fax: +65 6863 4077

On my last project I bought a cheap tube of silicone sealant, brand I forgotten since I threw the tube away after I finished my project. Green in color and safe for aquariums, as far as the packaging said at the time. However, this one gave off a vinegar smell as it cured.

**reiner09** · 7th Nov 2011, 21:33

okay thanks very much,i also felt that this might not be safe for aquariums, looks like i might have to scrap it off after all..

**stormhawk** · 8th Nov 2011, 09:31

Usually those with mold inhibitors etc, are not safe for aquariums. Plus, depending on your requirements, this particular sealant may not bond well with acrylic or glass. I read the technical sheet and you'd have to treat the glass surface with some other product, before this sealant will work.

Normal silicone sealant, nothing fancy, is the best for aquarium work. The smell however, is something I dislike.

**reiner09** · 8th Nov 2011, 12:51

Originally Posted by stormhawk

Usually those with mold inhibitors etc, are not safe for aquariums. Plus, depending on your requirements, this particular sealant may not bond well with acrylic or glass. I read the technical sheet and you'd have to treat the glass surface with some other product, before this sealant will work.

Normal silicone sealant, nothing fancy, is the best for aquarium work. The smell however, is something I dislike.

Okay, I will remove the silicon from the crack then..thanks very much..

**stormhawk** · 8th Nov 2011, 13:05

Just FYI, if the crack is on the canister housing itself, or at the motor housing, you might have to get those replaced instead, part for part. Within the canister chamber there will be some intense pressure, so if you try to DIY and repair the crack, it might get worst, or the silicone seal will not be strong enough to withstand the pressure. DIY canister filters show this problem easily.

**reiner09** · 8th Nov 2011, 13:14

Originally Posted by stormhawk

Just FYI, if the crack is on the canister housing itself, or at the motor housing, you might have to get those replaced instead, part for part. Within the canister chamber there will be some intense pressure, so if you try to DIY and repair the crack, it might get worst, or the silicone seal will not be strong enough to withstand the pressure. DIY canister filters show this problem easily.

Yea unfortunately, i bought a 2nd hand 2213 at $30 but realise there is a small crack at the outlet part of the canister body when i was washing it. I asked around the few lfs for a new 2213 canister body part but it is $45. It is totally not worth the money. I tried running the canister with the previous silicon i applied, it worked perfectly fine though..