Well. I'm a freaking idiot.

SO. I've been slowly but surely getting ready to put my refugium together over the past few weeks. I finally got the baffles put in a few days ago. I waited 48 hours for the silicone to dry, and then did a leak test. One of my baffles popped loose as soon as I started filling it up. So I decided to do some reading on the tube of silicone "duh..." Sure enough. At the end of the Instructions section it said "not suitable for use below waterline, or for aquariums." It's "GE II" silicone, I now know I need "GE I" So I slapped myself and began scraping it all off the tank and each baffle. Now I've gotten most of it scraped off but theres still little spots and smears left here and there. It says to use mineral spirits for clean up which I'm guessing is like paint thinner.

BUT, the tank I'm using for a refugium was built by my LFS lady and she used silicone to seal it up. Can I use paint thinner to clean up my bad silicone without damaging the silicone holding the tank together? OR can I just leave the little residual silicone without causing any harm to the water?

I don't know if the GE II is not suitable for aquariums because it will leach, or if it is unsuitable because it just can't hold the pressure...

 

Use a razor blade scraper.

 

Yea, I've done this, but because of the messy seal job on the tank, my silicone is all on top of the silicone she used in places, and I can't really scrape it off without scraping it all off... does that make sense?

 

I understand, sounds like you don't have much of a choice but to leave it. I don't think i would use paint thinner

 

GE Silicone II also has antibacterial crap in it which is bad for your tank.

Use a razor blade to scrape all the silicone off. If it can't go under water level fill the tank up with water for a few hours then try to rub the silicone off.

 

my experience has proven that paint thinner doesn't do anything for silicone once cured. Wet silicone also doesn't bond very well to already cured silicone, so if you do use a razor blade to get an end up on your silicone, you may be able to peel back all of the silicone you put down, like a scab, from the original silicone. worst case scenerio is that you have to cut into the original silicone a bit to get GEII off, and then go over that with correct silicone (and surrounding glass too). Which shouldn't matter since it's not a display fuge or anything right?

 

It would look messy, but you could put a thin layer of new GE I silicone over all your seals, therefore covering up and sealing off any leftover bad silicone.

 

I'm happy I saw this thread. I also bought GE Premium Waterproof Silicone II and I was ready to use this in a few days. Thanks for posting this issue! I'll trade mine in if possible. It's been about 3 weeks since I bought it at Lowe's and may have lost the receipt.

I'm a professional high end home painter and I actually thought all 100% silicone was underwater usable. But then again, we never silicone aquariums on the job

As far as removing it, there's no easy way to do this. No matter what tools you use, it's till a PITA, but like suggested, a glass scraper would help immensely. I wouldn't use Mineral Spirits or Paint Thinner (about the same thing) to clean with since once it's cured it's good for nothing. You may want to try naphtha or silicone wash. Just make sure to wash your tank THOROUGHLY with water and vinegar after that. Do it 3 times if you want to be sure.

Although Mineral Spirits or Paint Thinner and naphta will evaporate almost fully, there will be oily residue left in your glass and I can't think of a good reason to leave that there.

Good luck, and remember to wash with water+vinegar solution. You could also use Vinegar in its full strength (ie, no water added).

- Magnus.

 

Check in Lowes or Home Depot for Silicone Be Gone. Shop DAP 3 OZ. Silicone Be Gone™ Silicone Remover at Lowes.com
It's a special product sold for removing cured silicone. Be sure to thoroughly rinse afterwards. If you read the label on GE I you'll see that it is not for underwater use as well. Many people have used it without problem but for a few bucks more I'd get the stuff specifically made for aquarium use.