Repairing a 125 gallon aquarium

J

jeffreyrichard

Registered Member
Oct 25, 2012
4
0
0
I have a 20 year old Glass 125 (don't know manufacturer). This tank has developed a leaking bottom (bottom seam) ... 3rd time it happened. I is a "floating bottom in that the bottom outside edge sits inside the tank. In the past I've scaped the silicone out of the sexterior of the seam so the glass is flush ... I did NOT remove all the silicon joining the glass. I re-siliconed the joints and added pieces of glass and acrylic at the joints at various spots to provide extra bonding area. Now approximately 1/3 of each long joint (the 72 inch joints on the front and rear glass panals at the bottom) have this additional support.

The tank started leaking again after 3 months of use ... appears to be the middle of either the front or back seam ...

Ideas on better method? It could be an extreme amount of work to remove the glass/acrylic pieces from the seam to remove all the existing silicon ... any ideas for doing this (removing the glued/siliconed pieces)?

Do I have to remove ALL the silicone joining the bottom to the sides? That would be extreme due to the size ... I also wonder if the aquarium would loose structural integrity. Then there is the persion of getting the bottom back in again ...

A suggestion given to me was to add another bottom piece of glass that all side edges would butt up against (sit on top of) ... is this practical (cost)? How about adding a solid "seam" of glass (1 to 2 inchs wide) down the entire length of the inside bottom seams?

Thanks​
 
it just sounds like you need to re-seal the tank(by tearing out all, and I mean ALL of the silicone) and make sure you remove every little trace of it. New silicone won't adhere to new. Did you wipe the seams down with alcohol before laying down the new silicone? Did you make sure to compact the silicone down into the seams? I know it sounds like a lot of work, I've had to seal a 200 Gallon twice now.

Is the tank level? I have heard that if the tank is not level/uneven, it can cause the seams to break.
 
Manafel said:
it just sounds like you need to re-seal the tank(by tearing out all, and I mean ALL of the silicone) and make sure you remove every little trace of it. New silicone won't adhere to new. Did you wipe the seams down with alcohol before laying down the new silicone? Did you make sure to compact the silicone down into the seams? I know it sounds like a lot of work, I've had to seal a 200 Gallon twice now.

Is the tank level? I have heard that if the tank is not level/uneven, it can cause the seams to break.
Click to expand...

Thank you for the response ... not trying to be a wise guy, but this is kinda like "how to have $1 million and not pay taxes ... first, get a $1m ..." How would I remove all the silicone, given that I've glued (siliconed) about a dozen pieces of acyrilic and glass to the bottom, butting up against the front and back (attempted to privide better surface for adhering) ... some of these pieces are 4x4x1/4 glass ... best way to remove from the glass?

Also, does this call for entirely removing the floating bottom piece and reinstalling it? How best to go about that?
 
You don't normally have to remove the silicone that is used to assemble the bottom glass to the sides of the tank unless that silicone is physically missing.

Unfortunately, it will be extremely tedious to remove all the pieces of glass and acrylic that you have already siliconed into the bottom of the tank. If you want to do it right, you need to remove those pieces and all the silicone inner fillets. The acrylic pieces should be able to be removed relatively easy since silicone doesn't bond well to acrylic. The glass pieces may be more problematic.

Any chance you can post some pictures of current status of the repairs you have made and need to correct?
 
Floating bottoms are more likely to leak than traditional bottoms. They are generally only used on frameless tanks where the front panel is viewed all the way down to the bottom edge. Aesthetically it looks better, but it depends on the stand being able to support the bottom glass to keep the water pressure from pushing down on the silicone seam. That style of aquarium is more popular in Asia and Europe than the U.S. so I am guessing the tank was imported?

The main water seal is the seam on the inside corners of the aquarium. The silicone between the glass also forms a seal but it's main purpose is to keep the panels together with sealing being a secondary purpose.

You can probably fix the seal by stripping out the silicone on the inside corners, cleaning the area thoroughly with alcohol, and then applying a new silicone bead.

You did not mention it but I wanted to confirm that the tank is sitting on a solid topped stand that is of suitable thickness to provide support. Generally that would be at least 1/2" plywood or MDF.

Andy
 
dudley said:
You don't normally have to remove the silicone that is used to assemble the bottom glass to the sides of the tank unless that silicone is physically missing.

Unfortunately, it will be extremely tedious to remove all the pieces of glass and acrylic that you have already siliconed into the bottom of the tank. If you want to do it right, you need to remove those pieces and all the silicone inner fillets. The acrylic pieces should be able to be removed relatively easy since silicone doesn't bond well to acrylic. The glass pieces may be more problematic.

Any chance you can post some pictures of current status of the repairs you have made and need to correct?
Click to expand...

Thanks ... I'll post some pix when I completely remove the sand (still in tank ... all fish moved to an empty 70 gallon).

Any tips for removing the glass?
 
Narwhal72 said:
Floating bottoms are more likely to leak than traditional bottoms. They are generally only used on frameless tanks where the front panel is viewed all the way down to the bottom edge. Aesthetically it looks better, but it depends on the stand being able to support the bottom glass to keep the water pressure from pushing down on the silicone seam. That style of aquarium is more popular in Asia and Europe than the U.S. so I am guessing the tank was imported?

The main water seal is the seam on the inside corners of the aquarium. The silicone between the glass also forms a seal but it's main purpose is to keep the panels together with sealing being a secondary purpose.

You can probably fix the seal by stripping out the silicone on the inside corners, cleaning the area thoroughly with alcohol, and then applying a new silicone bead.

You did not mention it but I wanted to confirm that the tank is sitting on a solid topped stand that is of suitable thickness to provide support. Generally that would be at least 1/2" plywood or MDF.

Andy
Click to expand...

I'm 90% sure the leak is in the middle of the long seam on the bottom.

The tank is sitting on a 2x8 stand .. the tank has a drilled bottom for an overflow. The plastic frame (rim) extends about 1 inch below the bottom of the glass, so it would NOT be sitting on a flat surface regardless if I nailed plywood to the stand.

So I'm now thinking ... if I supported the bottom by building something under it would it help? I one issue I see is measuring exact enough so it could fit under the plastic rim but not keep the plastic rim from touching the wooden stand ... thoughts?
 
jeffreyrichard said:
So I'm now thinking ... if I supported the bottom by building something under it would it help? I one issue I see is measuring exact enough so it could fit under the plastic rim but not keep the plastic rim from touching the wooden stand ... thoughts?
Click to expand...

Do not support the bottom glass!! This style tank is meant to be supported by the plastic trim as it was designed.
 
Do not support the bottom glass!! This style tank is meant to be supported by the plastic trim as it was designed.
Click to expand...

That is not true. Floating bottom designs are designed to be completely supported across the bottom. A perimeter frame would only support the side panels and not the bottom which would be held in place only by the silicone connecting it to the side panels. Typically, floating bottom tanks are not made with frames.

A traditional bottom (where the side panels sit on top of the bottom panel of glass) is designed to be supported by a perimeter frame where the frame is actually supporting the bottom panel of glass.

This tank is poorly designed and probably why it consistently keeps leaking.

Andy
 
:iagree:
 
You must log in or register to reply here.
AquariaCentral.com
Top Bottom