Reseal aquariums; 2 different brands of silicone

[MarisaH]

Questions are in bold at the end if you want to skip reading most of the post.
 

Hi all, I got some good information to share if anyone plans on resealing a tank soon, but I also have a few questions for anyone who can answer.  Attached are some photos of the silicone I used & 54 gal tank I am in the process of resealing.

First here is some background info;

Last year in Early Spring 2023 I resealed a my 40 breeder with ASI aquarium safe silicone sealant via Amazon. That stuff worked great sealing wise, but took quite a long time to dry and fully cure. Kinda made me mad because it skinned so quickly but took forever to fully cure. (I usually do a test by putting a few beads of thick silicone on a piece of plexiglass. Then cut into it after certain periods of time to see if it fully dried or not so I can get a good estimate on if the silicone on the tank is actually fully cured or not.)

After reading through quite a few threads via Google, and based on comments on the Amazon review, people said they recommend waiting at least a week because this stuff takes a while to dry. I waited 7 days for it to fully cure. Then placed it in my garage, inside of my dog/children’s folding swimming pool to catch any water if it leaks. Then filled it all the way up & checked on it every day for leaks. I let it sit for about 6-7 full of water before I decided to drain it & bring it inside to use. 1 year of use later & it’s still doing great, no issues.

Around the same time (Early spring 2023) I started maintenance & care every week on a 10gal tank at my sister’s house for my 2 nieces & brother in law. Neither of them knew much about this hobby so we decided it was best for me to do it, so we could make sure the fish would actually be happy & live LOL.
 

My brother in law just decided to get into the hobby after a year of me doing everything & he upgraded from a basic 10gal to a 54 bow front. (Low key very excited he’s got the same hobby as me now. But my sister may not be. 😂) 

The bow front was free & needed to be resealed since it is exactly 20 years old & the seal was falling apart. He asked if I could reseal it since it wasn’t my first rodeo lmao. I said yes & purchased a difference silicone via Amazon since I wanted to see if this one worked better than the ASI. The new one I ordered was another popular brand recommend on other google threads. It’s called Selsil Aquarium Silicone Sealant & it states you only have to wait a few hours for it to cure, but 24 hours for it to “fully cure”. I know there is no way it will be “fully cured” in 24 hours. No thread on google or Amazon reviews gave much info on how quickly it dried for them so I decided to check the silicone via the test sample I do on a spare piece of plexiglass & @24 hours it was about 85-90% cured. The Selsil silicone definitely is curing a lot faster than the ASI silicone. (It took 2.5 days for the ASI to be 85-90% cured) My questions are; how long I should wait before doing the water test and also how long should I do the water test for? I have heard from people that waiting a week to dry is over kill, along with doing a water test for a week. What do you think? 
 

1st pic is the listing photo my BIL sent me before he decided to pick it up. 

 

2nd pic I took at my house showing how bad the silicone was. (I took other photos but they won’t upload on this post for some reason. They are showing a solid black image when trying to upload, so this is the best photo I got to show how bad the prior silicone was.)  

 

3rd/4th pic are screenshots of the ASI Silicone I used in early 2023.

 

5th/6th are the new Silicone I decided to use on the 54gal bow front. 
 

 

[jwcarlson]

I'd wait at least 10 days.  Two weeks if you can.  It, of course, comes down to how thick the beads are.... but if you're not in some big hurry taking some extra time will never hurt.  I've only ever resealed a couple of tanks, but one of them was a 125 and I was surprised how long it took to cure, though I did leave some thick beads.

One thing to look out for is expiration dates.  I believe it's possible that silicone that's too old might not ever cure fully.  I bought some silicone from amazon and it was very near if not already expired when I received it.  I ended up just going with GE Silicone 1 (whatever it's called now).

[HelplessNewbie]

Oh, I didn't know we needed to wait a week or so for curing. My hubby filled our resealed 65g tank with water (for leak testing) after only 2 or 3 days. Am I going to be in trouble? No leaks, as far as we know.

[MarisaH]

@HelplessNewbie usually most silicones take a minimum of 24-48 hours to cure, but some state via manufacturers to wait longer to be safe. I “think” I remembered reading somewhere from the ASI manufacture that they recommend 7 days to be fully cured. Don’t quote me though because that was over a year ago. 😂 That’s why with that one I waited so long to be sure.
 

This time around since I don’t have a lot of info about the new silicone I used, I made this post. (I couldn’t find a lot out about how long other people waited for dry time & water testing on this specific silicone. )
 

That is kinda why I made this post to ask others & also help future people who choose to use this silicone. (Selsil Silicone). I can’t really find anything about it anywhere online other than seeing how people rate it on Amazon which kinda sucks. 

Then as far as water tests go I’ve seen some people buy a brand new tank with an original manufacturer seal from petco/petsmart etc & fill it same day with no issues, no leaks nothing. Even 5 years later the tank is fine…..But I have also seen people do that & have a leaking tank within 0-6months.

Others reseal a tank themselves, wait 2 days, & do a water test for 24 hours & then they never have an issue. Then others do that & have a leaking tank within a year… so I guess what I am trying to say is that It all varies on tank size, bead thickness, silicone used, how well you removed the old silicone, LUCK, etc. 😂😅

 

[MarisaH]

@jwcarlson

I agree, I think longer is always better. Better to be safe than sorry as far as waiting for the silicone to fully cure. I am gonna try to do some more research on this silicone before I actually do the water test.

I do remember reading when I bought the ASI silicone that some people said it was either very close to expiration or already expired by the time they received it. Luckily I got one that was fine when I purchased it in 2023. I made sure to double check the date on the Selsil silicone I just purchased before I ever put it on. It expires 2025 luckily. I’m glad you mentioned that because some people don’t know that silicone expires! 

[jwcarlson]

You can go down some DEEP rabbit holes regarding silicone and silicone curing.  Especially on the reef forums which is where I ended up when I was doing some research.  I don't think it's rocket science, but I am not exaggerating much when I say that some reefers think it is.  😄