Gold Label Underwater Sealant, 290 ml, Black

I have ordered several of these, over the years, I like to keep one in, as I have a pond with a butyl liner, this stuff is brilliant, says what it does on the tube. It's got me out of a scrape, when rats have chewed my liner a few times. Speedy and safe in the water with fish. Easy to use ,but I would recommend gloves as it sticks really well.

This product is amazing and I wish I discovered it sooner. My pond has always had a slow leak since I bought the property and it was already there and it was annoying, but I lived with it. However recently I was working by the side of the pond and dropped a saw which tore big jagged holes in the liner.... I was mortified and the level dropped by half within hours. After lots of research and not much luck and almost resided to the fact I was going to have a mammoth task ahead redoing the pond, I discovered this product. Skeptical but I tgought for the price, worth a shot. Amazing. Easy to apply, does exactly what it says on the tube and whilst I did it, I went around and covered a few tiny holes at top and pond is the fullest and best it's looked since I have moved in and staying full. For the large holes from the saw teeth, I bought a tiny pond liner from here, which was cheap and cut a small patch, like repairing a bike tyre and it's worked a treat. £20 spent in total and pond like new.

A very good product and has worked to seal the holes in my pond, however anyone who suggests this can be used under water must have strange mystical powers enabling them to do so. I tried using it under an inch or two of water and the sealant just floated away like a sea slug. However, definitely works a dream on fully drained pond even if surface still damp.

This is brilliant stuff, almost like liquid liner. I fixed a hole in a liner by applying it thickly (e.g. 2 mm thick) to a patch piece of liner, placing the patch on the hole, pressing gently around the side of the patch (not in the middle, there needs to a thickness of goo) and hey presto, done. I also tried a test piece and can confirm that this stuff is _very_ difficult to remove.

We used this on the outside water feature which had cracks init worked great sealed the cracks and the leaks are gone would recommend

Having managed to slice a 2cm hole on a crease in my outdoor pond liner I was unsure how to repair this, a patch was not possible. I did drop the pond level to access the damage so can't comment on underwater use. I inserted the nossel through the liner to hopefully block the hole from behind and also added more on the surface. It might not look pretty but you can't see the repair when the pond is full. The repair seems to be completely watertight so job done. Obviously can't speak for longevity time will tell. It's an excellent product but I found it difficult to get out of the tube, warming it up in hot water helped. Take care it sticks to everything!

Disappointing results - does not stick if surfaces not completely dry. Drained pond for 2nd attempt and stuck patch carefully in accordance with instructions leaving good bead & not pressing flat. Patch stuck very well but minor leak through bead - stuck 2nd patch over top but still very minor leak.

I have purchased both the clear and the black. For some reason the clear seems not to be so good to use for wet places or under water. The black I found to be much better. Strange! I have used them to seal edges around the pond and as an adhesive in the pond. Does a decent job. Wouldn't get the clear again though.