# Used Tank Silicone - Replace or Not???



## kazfish (Aug 1, 2012)

I just purchased a used 150 gallon tank. It was set up with water before I bought it - so it does not leak. But after bringing it home and inspecting it closely...the silicone along the front corners is broken down a bit. I believe the prior owners used a magnetic algae scrapper, hit the silicone seal repeatedly and created jagged notches in it. It is also pretty stained and in spots is not adhering as well as it should.

So, what should I do?

1. Cut out all of the old silicone along all 4 corners and replace it down to the bottom section...which is in perfect shape?
2. Cover the old silicone with new silicone as a precaution and to even out the look of the seam for appearance improvement?
3. Leave the silicone alone because the tank does not leak.

Any suggestions would be appreciated.

Kaz


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## CjCichlid (Sep 14, 2005)

Without seeing the tank it's hard to say..

With that said, I'd probably just leave it be. If you do end up resealing it, you have to reseal ALL the seams, not just the sides. Silicone does not adhere to itself very well so option #2 is a no go.


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## kazfish (Aug 1, 2012)

Thanks Chris - I know it is difficult to comment without seeing the tank but I do appreciate your input. I guess I am trying to understand if I will be opening myself up for leaks more by taking off the old silicone and replacing it or by just leaving it?

And are you saying that if I take off only the sides down to the bottom section - that the seam I will create where the sides meet the bottom is a "no-no"?

Thanks

Tom


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## jcabage (May 29, 2012)

kazfish said:


> I guess I am trying to understand if I will be opening myself up for leaks more by taking off the old silicone and replacing it or by just leaving it?


If you reseal the tank correctly, that will most surely be your better leak protection. If you haven't attempted this in the past, however, I wouldn't let my 150 gallon show tank (if that is the goal) be the experiment.



kazfish said:


> And are you saying that if I take off only the sides down to the bottom section - that the seam I will create where the sides meet the bottom is a "no-no"


In general, when resealing a tank you will want to strip and re-apply silicone to all of the seams. Even though the bottom is in good shape, the silicone will not bond to the new strips applied to the sides.

It is of course a judgement call after seeing the tank, but having been put in the same situation in the past, I usually forego a reseal unless it seems completely necessary.


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## kazfish (Aug 1, 2012)

That's exactly the input I was looking for. It would be the first tank I have resealed and it is my show tank. I just dread having it set up for 6 months to a year and then have a leak start because I didn't reseal now when I had the chance. Not an easy decision. That's why I'm trying to thoroughly understand if the resealing process by an amateur....me.....might CAUSE a leak to happen versus the chance of it leaking by leaving it alone. That is my dilemma. Also, resealing it would certainly make it look better than it does now.

Is your "completely necessary" directive to mean "when it leaks"?

Thanks!


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## lilscoots (Mar 13, 2012)

You are not likely to cause a leak unless you cut into the silicone providing the "butt joints", the silicone actually holding the tank together. Resealing isn't all that difficult. Getting a nice looking seal can be if you have no experience caulking with silicone. If the current silicone is going to bother you, what I would do is look for a really cheap, or free tank on craigslist in your area, buy it and practice cutting out the old silicone, and resealing it. as many times as you want until you feel comfortable working with silicone, then have at your 150.


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## kazfish (Aug 1, 2012)

ok good advice. So it sounds like taking a razor blade and cutting the jagged edges away to make it look better would not be harmful necessarily to the overall seal. I think if I do that I'll feel better about the look of it.

Otherwise it sounds like I'm just inviting a whole bunch of work that might not have the biggest payoff for me?

Thanks again.


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## spotmonster (Nov 23, 2006)

I had the same dilemma on a 180 i picked up used. I tore the tank down when i picked it up, so I knew it did not leak. but it had some edges that weren't 100%. I chose to leave it since I knew that id did not leak. That was 3-4 years ago.

I would say an amateur could risk causing a leak by a 1st time reseal. I have resealed a small tank before with no issues, and still decided to leave the 180 alone. In theory a a big tank is no different to reseal. But in reality, you need to work quicker and it's much harder, because you have to be able to "reach" everything properly in that time frame. And if it's indoors, you will need a mask and ventilation.

Having said all that, it just depends on "HOW BAD" it actually is. Pics would help.


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## kazfish (Aug 1, 2012)

Yes, pics would help...and I have 4 of them to share. Honestly, I can't figure out how to attach them...could use some help with that too!!


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## Steve C (Oct 9, 2011)

kazfish said:


> Yes, pics would help...and I have 4 of them to share. Honestly, I can't figure out how to attach them...could use some help with that too!!


You need to host the resized pics somewhere, I use Imageshack myself (its free) but there are other ones out there as well. Resize and host the pic there, then copy&highlight the URL of the picture, then in your reply here on the site click the IMG tag above the reply box. In between the IMG tags that appear when you click that tab you will then paste (Ctrl and V) and that will post the URL of your picture which you copied. Pic will then show on this site.


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## kazfish (Aug 1, 2012)

Here are the pics. Did I do it right?


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## Deeda (Oct 12, 2012)

Your pics are not showing. Check out the link in my signature for how to post pics.


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## Steve C (Oct 9, 2011)

Here ya go, fixed it for ya. The other two wont show so I'm guessing the file size is probably too big and just timing out on them.
.
.


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## lilscoots (Mar 13, 2012)

if that's the worst of it, I'd leave them be.


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## kazfish (Aug 1, 2012)

Thanks for helping me with the photos and commenting on the silicone as well. Yes, that is the worst of it....I actually already cut the jagged edges away to make it a bit more visually appealing. Wish me luck!


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## lilscoots (Mar 13, 2012)

The seal in the one pic is a bit sketchy...that pic hadn't loaded when I commented before. While the inner seal doesn't hold the tank together so much, it does add a some security to prevent leaks...I'd probably reseal it, but I've resealed quite a few tanks, worked as a painter for 11 yrs, and am very comfortable using silicone.


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## BillD (May 17, 2005)

I would reseal that tank. Aside from the fact it looks poor, it will only get worse. the reality is if the tank was built properly, it won't leak even without the inner seal. Since the tank is large, it will take a while to strip the old silicone out and properly clean it. As well as mentioned, the reseal needs to be done quickly. To do this have a plan in place and the sequence for the seams. Have a friend to help so you can turn/flip the tank to make it easier. If you aren't comfortable using a caulking gun, you can do as McDaphnia suggested, and buy the cheapest caulk you can find and practice on a cardboard box.


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