Silicone myths or real issues…

[Orthopod]

A buddy of mine used these 2 silicones in his tanks and has had no issue with his fish - 1 says mold resistant and the other says mold free.

It has been beaten into me that mold additives kill fish but at least in this case doesn’t seem to be the case .

Here are the 2 products he used. Thoughts?

 

[tlindsey]

It has been beaten into me that mold additives kill fish but at least in this case doesn’t seem to be the case .

I've read once here years ago that someone used mold resistant GE silicone and swore it didn't affect their aquarium.
I have a aquarium setup around 5 years but used the pure Silicone GE 1. I would never use a mold resistant Silicone product.

 

[wednesday13]

Still a craps shoot for debate, some say the mold inhibitors are fine but most say there not… ive personally used ge2 mold resistant and had ill effects in my early years of tank building. Ill never use it again lol… it took a good 4-5 months before it started making my water “toxic”… some fish lived being pulled to another tank, others perished. Never had an issue with ge1 in all my yrs.

 

[jjohnwm]

Back in the day, the anti-mold additive in silicones targeted at bathroom work was arsenic...so, yeah, I tended to avoid the stuff. I knew folks who were paranoid like me, i.e. who changed water constantly, and who got away with using the toxic stuff, but other people with more...shall we say "casual"...water change regimens sometimes had mysterious problems. I always stuck (pardon the pun...) with pure 100% GE Silicone I, with complete satisfaction. Then, as today, the known-to-be-safe product was readily available, relatively inexpensive and easy to work with, so...why on earth take chances?

In the first of the two pics above, the product is stated to be 100% silicone; so far, so good. But...it also says "low odour". Apparently, there are silicone products that cure by the release of compounds other than the familiar, comforting acetic acid (vinegar) which gives Silicone I its charming aroma. Is this stuff in the pic one of them? And does it matter? Beats me, and I don't care; Silicone I works like a charm and is safe; why experiment with this new stuff?

The second pic? The tube reads "Advanced Siliconized Something-or-other"...maybe "sealant"? We're moving further and further from my comfort zone now; why on earth would anybody mess around with this goop? Your buddy claims to have success with it. How much did he use? For how long? And how does he define "success"; his fish aren't all quite dead?

I won't claim success with a silicone for tank building unless it has proven to be safe and effective for a decade or so...just sayin'...

So, again...why experiment?

 

[fishdance]

The anti mold additive is a long chain organic molecule. Very easy to remove with carbon filtration. It has a half life so it will decline over time and faster dilution with more water changes without carbon.

The amount of anti mold additive is minuscule compared to the volume of silicon which in turn is minuscule compared to the volume of your fish tank. Thicker and longer beads of silicon will contain more chemical in proportion. Conversely nano tanks will have stronger adverse effects than mega tanks.

The speed of silicon type technology is astounding. Stronger tensile strengths, higher flexibility (modulus), faster cure times, underwater use, longer product guarantees, UV resistance, etc etc. Additionally PE is becoming more common in commercial aquarium applications than silicon nowadays because new PE will stick to twenty year old PE unlike silicon.

 

[fishdance]

With the range of products available now, it's easy to choose the specifications you desire including colour. But to answer your question directly, I've often used anti mold silicon on lots and lots of tanks without issue.

Sometimes price becomes a factor when buying in boxed carton lots.

 

[jjohnwm]

With the range of products available now, it's easy to choose the specifications you desire including colour. But to answer your question directly, I've often used anti mold silicon on lots and lots of tanks without issue.

Sometimes price becomes a factor when buying in boxed carton lots.

The anti mold additive is a long chain organic molecule. Very easy to remove with carbon filtration. It has a half life so it will decline over time and faster dilution with more water changes without carbon.

The amount of anti mold additive is minuscule compared to the volume of silicon which in turn is minuscule compared to the volume of your fish tank. Thicker and longer beads of silicon will contain more chemical in proportion. Conversely nano tanks will have stronger adverse effects than mega tanks.

The speed of silicon type technology is astounding. Stronger tensile strengths, higher flexibility (modulus), faster cure times, underwater use, longer product guarantees, UV resistance, etc etc. Additionally PE is becoming more common in commercial aquarium applications than silicon nowadays because new PE will stick to twenty year old PE unlike silicon.

Honestly, my reaction to most of that is "That's nice; so what?" Sure, everything is more advanced today than it was in days past...but most of those improvements you listed are essentially meaningless to me, and to many others. It's stronger...but how much is that worth? Silicone was more than strong enough. Cures faster...okay for the instant gratification crowd. Cheaper? Great...but I'll believe that when I see it. Applies underwater? Might be useful...

But..."new PE will stick to twenty year old PE unlike silicon"?!?!?! To me, that is a gamechanger! How about silicone; does the new miracle goop stick to old silicone? I gotta try this stuff!

So, if the question is "do anti-mold additives make modern sealants unsuitable for aquarium use?"...the answer would be an unqualified unambiguous "probably not"...

But none of this changes my assertion that...if the question is worded "My buddy did no research and used up a few tubes of whatever crap came to hand in his fishtank; was that bad?"...my answer would still be "Yeah...I think it might have been, and I hope he gets lucky".

 

[Orthopod]

Honestly, my reaction to most of that is "That's nice; so what?" Sure, everything is more advanced today than it was in days past...but most of those improvements you listed are essentially meaningless to me, and to many others. It's stronger...but how much is that worth? Silicone was more than strong enough. Cures faster...okay for the instant gratification crowd. Cheaper? Great...but I'll believe that when I see it. Applies underwater? Might be useful...

But..."new PE will stick to twenty year old PE unlike silicon"?!?!?! To me, that is a gamechanger! How about silicone; does the new miracle goop stick to old silicone? I gotta try this stuff!

So, if the question is "do anti-mold additives make modern sealants unsuitable for aquarium use?"...the answer would be an unqualified unambiguous "probably not"...

But none of this changes my assertion that...if the question is worded "My buddy did no research and used up a few tubes of whatever crap came to hand in his fishtank; was that bad?"...my answer would still be "Yeah...I think it might have been, and I hope he gets lucky".

Lol - that may be the gist of the above but with GE changing their labeling and adding unsafe for aquarium on both bottles now and all the other assertions And arguments pro and con I have seen, I for one am interested in the debate. I still like to have my debates here and not on some random Facebook thread.

Talking to him he used an entire bottle of the sealant one to line his bulkheads and has used it in the past to seal tanks. He keeps rays and other monster fish, probably like many of us.

i was always a GE 1 user but they relabeled it and it may now too have new additives from what I am told.

 

[jjohnwm]

Lol - that may be the gist of the above but with GE changing their labeling and adding unsafe for aquarium on both bottles now and all the other assertions And arguments pro and con I have seen, I for one am interested in the debate. I still like to have my debates here and not on some random Facebook thread.

Talking to him he used an entire bottle of the sealant one to line his bulkheads and has used it in the past to seal tanks. He keeps rays and other monster fish, probably like many of us.

i was always a GE 1 user but they relabeled it and it may now too have new additives from what I am told.

Well, the top one is 100% silicone; adding anything would, by definition, mean that it's no longer 100%...but I certainly see your point.

The bottom product? What's even in it? It's "siliconized"...maybe that means that it has a few percentage points of silicone added to it? When silicone becomes the additive, rather than the main ingredient, I would need a bit more of an incentive to use it than merely "Well...it was on sale..."

I long for the good old days, when you asked for silicone and the only question was "Will that be with or without arsenic?"

 

[FJB]

Ignorant here...
What is 'PE silicone'? - When I google it, it just says that is an estimated "Profit to Earnings ratio', applicable to any product. However, when used as in post #5 above, it sounds as a brand, or a type of silicone. Could somebody more knowledgeable explain?