Silicone caulk goes bad

Well I learned something new. I never knew Silicone caulk goes bad but apparently it does. When it does it no longer cures and hardens. I just found this out the hardway. A tank I sealed yesterday is still wet. Search of the internet shows this is indeed what happens.

Never thought a sealed tube of caulk would go bad. Just checked the tube in the garbage and sure enough date stamp says.. best buy 01/2022. Bit ticked because I just bought that a few months ago.

So now I need to remove all that wet caulk.. clean it up and reseal. What a royal pain.

Lesson to all.. check your caulk when you buy it and before you use it. Im really surprised by this as I know I used caulk in the past that was laying around a few years.

Researched further showing mfg say 1-2 years shelf life.

What a bummer.

Now I am going to be leery always. I just bought a 4 pack of caulk earlier this week...
Received it yesterday and checked the date..

Made..
Attachment 139321

Expires
Attachment 139322

I buy in bulk to save $$ but no way I will use 4 tubes in the next 4 months.

Oh man Al, that sucks. I have four tubes of black Silicone and hope they are good! I thought Silicone was good forever :(
Pat

What a mess. I've seen it harden in the tube but I had no idea it wouldn't cure after a certain time...

Its unbelievably difficult to clean up. I used a glove to get the bulk.. smeared everywhere...tried alcohol , didn't work. Tried vineger..nope. used a razor which kept slipping out if my hands.. some reports said acetone..which worried me because of the plastic frame. But thats what I used... it seemed to work after alot of rags and acetone.I washed the tank with alcohol let dry and just resealed. I don't know if will hold. Time will tell. The first sealing was picture perfect.. this time it looks like junk... I made the bead bigger in the hopes that it will help hold given the history. All this work for a green water tank.. what a pain.

Yep, I had some that I bought from Amazon that came in expired. I ended up just buying GE silicone 1 at HD instead. Wet silicone is a nightmare to clean up.

What a nightmare. I never looked for exp dates. Will do in the future. Never had much luck resealing tanks, they always leaked afterwards usually days after sealing when restocked with fish.

Hey Al, I was just told by one of the LFS that the tanks that are sealed with the black silicone are newer tanks if your buying one and the best silicone, is this legit, with so many new tanks of today still they show clear silicone still, and if the black silicone is the cat's meow, what name does it go under, I would like to reseal a tank and would get some and try it, ever heard of it. Thanks

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Originally Posted by Marty

Hey Al, I was just told by one of the LFS that the tanks that are sealed with the black silicone are newer tanks if your buying one and the best silicone, is this legit, with so many new tanks of today still they show clear silicone still, and if the black silicone is the cat's meow, what name does it go under, I would like to reseal a tank and would get some and try it, ever heard of it. Thanks

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Hi Marty,
I have a feeling that LFS is mis-informed. Most glass tanks use clear silicone caulk as its less obtrusive than Black visually. I was just at petco this past week picking up a few tanks and all have clear silicone.I have never used a black silicone before, but I can't imagine it would be meaningfully different than clear.



I have used this brand..

Apel

Attachment 139357

It worked great. The only reason I didn't buy it this time was it was not in stock.



hth, al

Quote:

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Originally Posted by Marty

Hey Al, I was just told by one of the LFS that the tanks that are sealed with the black silicone are newer tanks if your buying one and the best silicone, is this legit, with so many new tanks of today still they show clear silicone still, and if the black silicone is the cat's meow, what name does it go under, I would like to reseal a tank and would get some and try it, ever heard of it. Thanks

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Hi Marty - the black in the silicone is carbon black which has no other functional property than turning it black.