Converting pool to pond

[szinla]

My house has a shallow pool covered in 1 x 1 tiles with grout; this covers a concrete base. My plan is to convert this into a coy pond.

The pool has a leak, and so I'd like to seal it with something that 1) is clear and 2) will not be toxic to fish. Any suggestions? Thanks. Steve in Los Angeles

[VALENT]

That should make a nice koi pond. Try sealing the leak with hydraulic cement.

[szinla]

Thanks for the response. Hydrolic cement doesn't sound clear. Is there another, clear option?

[giddonah]

You're going to drain it? Try silicone.

[VALENT]

What is the necessity of it being clear? Underwater, it is very unlikely that it will be seen.

[Sweep]

I'm not sure if you are trying to seal a leak or cover the entire pond with a clear coating.

If you are looking for a sealant for a leak, because of its relatively low adhesion, silicone sealant is not the best choice for underwater use unless it is mechanically held in place and under compression.

For the best underwater sealant you should use a two-part polysulfide. Next choice would be one-part polysulfide. Next choices would be two and then one-part polyurethane. Two part sealants are difficult to find in the retail market so you might have to settle for a one-part polysulfide.

The attached gif file shows the features of the 3 synthetic rubber-based adhesive sealants.

Here is a good discussion of marine sealants.
http://www.boatus.com/boattech/casey/35.htm

If you are looking for a clear pond coating you should google for "koi pond sealant" or "koi pond coating". You will find a lot of information although I'm not sure of the technical relability of the claims and some chemicals are difficult to have shipped from the UK.

Koi ponds are a lot of work to build and operate. It's a big committment.

[ODDJOB]

Loc-tite makes an epoxy that is clear, we use it to repait chips in concrete.
after it dries it looks just like glass.