I used silicone with an anti-fungal chemical

[Atu]

Last night I was doing some sump renovations, when I finished I realized the silicone I've used had a small label that read "anti-fungal" (I'm from Argentina and it's in spanish actually but I'm translating). I bought the same brand I always use, but this time my usual shop was closed so I went to another and ask for the same product, I didn't even check it.. I was having a bad day, and it was just starting. The clerk hand me a version with an anti-fungal which looks almost the same as the regular one.

When I was about the turn on the pumps I realized my mistake, I decided to act quickly and undo all I have done. I stayed until 3 am removing all the silicone I could from the sump with a box cutter and ethanol. I turned on the pumps and went to sleep. Today everything looks fine, I have a 500 gallons system I'm sure that helps. I think I dodged a bullet here.

So, why am I posting you might ask? Well, last year I manage to convince my college to build 2 reef tanks using some cube tanks they had laying around. I work and study in the University of Buenos Aires, which is a public funded school, so not a lot of money to go around (you might also have heard about the economic situation in Argentina). I'm part of the zoology department and the idea is to use the aquariums so the students can study the animals alive, instead of dead like they usually do. Buenos Aires has no sea coast so a lot of small critters from our aquariums are really useful for our students (amphipods, asterina stars, bristle worms, etc.).
I plan to make a thread about it in the future, but the reason I'm writing this here is because I realized that the silicone the college gave me to build the aquarium is the same I used yesterday with the anti-fungal chemical. I was having trouble maintaining easy corals from my own system (rhodactis, actinodiscus, calaustrea. The rhodactis are fine actually, but the actinodiscus died which is weird). I blamed it on the custom build lights not being good enough.
Also, I had a problem with the previous pump which I suspect was leaching copper, so when some asterina stars started dying at the start (which had never happened in my home aquarium) I blamed it on the pump and changed it.


According to the box the chemical compound in question is

4,5-Dichloro-2-n-octyl-4-isothiazolin-3-one​

Could it be that this problems are due to the antifungal in the silicone? It's been over a year, should I still worry and re-do the overflow boxes (where I used that silicone), or it had been long enough? Would something like activated carbon help? Can it still be leaching into the water after all this time?
One of the cubes have a couple of clownfish for months now and they never had any problems. I've amphipods and copepods by the thousands, lot of bristle worms also.

Thanks for the help and sorry about the long post

 

[KrisReef]

I think this answers your question; "I've amphipods and copepods by the thousands, lot of bristle worms also."

If the microfauna isn't suffering the amount present is insignificant. Run carbon and don't worry about it, imo.

Maybe you won't get algae growing on the silicone seams, but I wouldn't expect any other observable impacts.

 

[Randy Holmes-Farley]

4,5-Dichloro-2-n-octyl-4-isothiazolin-3-one​

I do not know how much might come out of silicone, or how much is needed to be a problem, or exactly what problem is most likely, but that specific chemical should be readily removed by skimming and granular activated carbon, so those methods may override any tox concerns.

 

[Atu]

Maybe you won't get algae growing on the silicone seams

Actually there is even filamentous algae growing on top of the silicone in some parts, I've even seen a spot of coralline algae!

if the microfauna isn't suffering the amount present is insignificant

I guess you are right about this

but that specific chemical should be readily removed by skimming and granular activated carbon

Thank you Randy! This is great to know, it puts me at ease

 

[T4ylor]

ive done this too yesterday i added silicone around my bulkheads a some on a leaking sump divider. i realised after that the silicone was a mold and mildew inhibitor and not safe for aquatic life. ive been told that its no big deal and to just remove it and reseal it and also been told i need to replace everything that i applied silicone to and rinse all my rocks and sand and run carbon???

 

[Randy Holmes-Farley]

ive done this too yesterday i added silicone around my bulkheads a some on a leaking sump divider. i realised after that the silicone was a mold and mildew inhibitor and not safe for aquatic life. ive been told that its no big deal and to just remove it and reseal it and also been told i need to replace everything that i applied silicone to and rinse all my rocks and sand and run carbon???

I cannot see a convincing rationale to remove things the silicone has merely touched, and even other stuff in the aquarium. I would use GAC and skimming.

 

[T4ylor]

I cannot see a convincing rationale to remove things the silicone has merely touched, and even other stuff in the aquarium. I would use GAC and skimming.

so id be perfectly fine with removing the silicone and running some carbon?

 

[Randy Holmes-Farley]

so id be perfectly fine with removing the silicone and running some carbon?

I'm only giving my expectation, but that is my opinion.

 

[KrisReef]

I don't know how many times I have used caulking with "inhibitors" in my bathroom and kitchen and after a brief time the caulking will have red or black algae or bacteria, or some other gunk growing on the seal just like regular caulking, or silicone that doesn't have these inhibitors added. It seems likely that if there were enough additives to prevent stuff growing that the seal would fail instead of hold like it is supposed to?

 

[jda]

Over the years, this has happened and been pondered many time. Some swear that they have the issues indefinitely. Some swear that they never have any problems at all. There are no absolutes here.

I would do what is organic to you and your personality. If you are always going to worry about it, then get it out. If you are OK with just observing and putting it in the past, trusting in the belief that this will pass and are able to move on, then you are good. You DO NOT want to have an issue a year from now and wonder if letting the carbon go too long while you were on vacation was the problem - it probably was not the problem, but if you will wonder then just remove the stuff now.

 

[Atu]

In my case in my home system I removed all from the sump walls before it ever touched the water. I never noticed any problem in there.

In the college aquarium in the other hand I did have problems, but I can't be sure it was the silicone. I do not think it was in any case. I think I was having metal contamination problems due to the old pump I mentioned in my initial post. I bought some cuprisorb and ran it for 6 weeks and things look a lot better now.

Coralline algae and hair algae grows on top of the silicone I used, so it does not look like a problem for them.