Seesure Seesure
  • Just popping in
  • Just popping in
  • Joined: 30/8/2008 17:20
  • From Gloucestershire
  • Group: Registered Users Basic Membership
  • Posts: 14
  • Posted on: 7/8/2009 9:19
Sealing a leaking tank #1
Have been away on holiday for almost 3 weeks and whilst I was away my mother (who was house sitting) text me to say the fish tank was leaking.

Anyway when I returned I could see that the water level had dropped by an inch or so. All seemed to have stabilised when I returned, however overnight (last night another inch or so has disappeared.

Now the tank is built in and I don't fancy trying to dismantle half of my office but was wondering if

1) If a tank sealant was the way to go ( I believe you can get special ones for fish tanks

2) would that tank have to be totally dry to apply the sealant

Advice and suggestions would be greatly received - especially as access to the tank is very restricted..
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Lynda Lynda
  • Just can't stay away
  • Just can't stay away
  • Joined: 6/6/2008 15:01
  • From Buckinghamshire
  • Group: Registered Users Basic Membership
  • Posts: 81
  • Posted on: 7/8/2009 10:10
Re: Sealing a leaking tank #2
you need to find the leak before you can decide what to do. Is it the seal or an external filter/pipes. until you know where the problem is you can't fix it.

If it is the seal on the tank it depends how bad it is. I had a pin hole leak in my seal and was able to fix it from the outside of the tank with tank sealent.

but my leak wasn't big enothe that I saw a drop in water. You need to find the leak
Seesure Seesure
  • Just popping in
  • Just popping in
  • Joined: 30/8/2008 17:20
  • From Gloucestershire
  • Group: Registered Users Basic Membership
  • Posts: 14
  • Posted on: 7/8/2009 12:13
Re: Sealing a leaking tank #3
As you can see it's built in, water is leaking on to the left hand wooden ledge, however I've managed to peak underneath and there appears to be quite a lot of damp at the rear right hand corner, so I'm guessing the water is travelling along to the left.

The only way I can think of sorting out the problem will be to get some cheap plastic tanks, relocating the fish to those, draining the tank and leaving it for a couple of weeks to dry out and then somehow trying to apply sealant internally all round.

There is absolutely no way I can get access to any of the external edges without a serious amount of damage to the property structure. Also trying to get round to rear would be impossible as they tank must weigh a lot as the glass is at least 10mm thick.... And I wouldn't be able to shift it without a fair bit of help

It's definately the seal (somewhere) as I have no external pumps / pipes to worry about.

But does the tank have to be bone dry for the sealant to adhere?
Howard Howard
  • Marine Adviser
  • Marine  Adviser
  • Joined: 14/1/2007 18:47
  • From Surrey
  • Group: Registered Users Advisers
  • Posts: 3799
  • Posted on: 7/8/2009 12:27
Re: Sealing a leaking tank #4
Yes , pretty much ...

Your plan is the best , drain it , relocate the fish ( you won't need to leave it two weeks to dry out ) and re seal ...

Once you find the leak , if you can strip the silicone off that length and re apply as new silicone doesn't stick very well to old in theory ..... however ...

If it was me , i'd buy a couple of tubes of aquarium silicone ( don't use the stuff from the DIY shop as it has fungicides in it which poison the fish ) and just go over ALL the joins in the tank with another nice thick layer , leave to dry and it ( should ) be ok.

Good luck , that's my worst nightmare ...
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Keep your friends close , but your anemones closer ....
Seesure Seesure
  • Just popping in
  • Just popping in
  • Joined: 30/8/2008 17:20
  • From Gloucestershire
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  • Posts: 14
  • Posted on: 7/8/2009 13:19
Re: Sealing a leaking tank #5
Many thanks, I'm going to have reseal the whole tank to make sure I've done the spot which I can't identify easily. Was thinking of leaving it for a couple of weeks to dry to save having to remove 60+kg of gravel which hold water for a while, plus all the rocks and stop etc.