Sprung a leak

[hotspurdotus]

My pond construction was going very well until this past weekend, when I realized I was losing water much too quickly. After some sleuthing, I realized that have a leak somewhere in the pipe that connect the two pools of my pond (picture is taken from above)

On the top of that picture you see the pre-existing concrete pond; I had to chisel a hole through it in order to feed the pipe through. Here's the view from inside the concrete pond

As you can see, I've drained the upper pond pool, removed the liner and capped the bulkhead while I'm troubleshooting the problem. The leak may be occuring because of a bad seal of the liner in the bulkhead; water is definitely leaking out of the liner once it reached the height of the bulkhead. I've attempted to seal and smooth the area with outdoor caulk but no success so far.

Any advice on solving the problem with the seal around the bulkhead? I had also considered using the black waterfall foam to seal around the pipe between the pools(as shown in the first picture) ; good idea?

Thanks for any suggestions.

 

[koiguy1969]

silicone....100% pure silicone sealer....get rid of the caulk and redo with silicone. RTV silicone, aquarium silicone etc...

 

[hotspurdotus]

I will do that. I'm not an aquarium guy, so it didn't occur to me. Thanks.

silicone....100% pure silicone sealer....get rid of the caulk and redo with silicone. RTV silicone, aquarium silicone etc...

 

[gooman]

the previous post is correct, remove the sealant. But where they went wrong is the type of sealant. Aquarium sealant is typically acetoxy silicone and will eat porous substrates such as stone, concrete, block brick. You should use a natural cure silicone designed for this application. I recommend Dow Corning's 790, should get at least 20 years out of the sealant. Also you will need a backer for the joint, use open cell backer rod(denver foam or tundra foam), or a spray polyurethane foam which may act as secondary seal.

 

[addy1]

Try 5200 marine sealant, has to be given time to dry but it does seal.

 

[bsr8129]

after 2 months i hope he has fixed the leak

 

[addy1]

after 2 months i hope he has fixed the leak

LMAO obviously we did not notice the date! and you are so right

 

[digginponds]

LMAO obviously we did not notice the date! and you are so right

Well since the thread was bumped I'll add my 2 lousy cents...Waterfall foam is NOT A SEALANT,it is only to correct waterfall flow. Or it may hold a few small rocks in place................Alot of people make the mistake of thinking it is a good sealant!

 

[addy1]

Well since the thread was bumped I'll add my 2 lousy cents...Waterfall foam is NOT A SEALANT,it is only to correct waterfall flow. Or it may hold a few small rocks in place................Alot of people make the mistake of thinking it is a good sealant!

It did not help with our leak at all...........lol the 5200 finally fixed it.