How to reseal a cement ornamental pond?

[BrianK]

I'm looking to reseal a largish (approx 16 sq m) ornamental pond. It is cement in construction, but the pond bottom and walls were painted 6 or 7 years ago using Crommelins pond sealer. The sealant coating on the bottom surface of the pond is showing significant deterioration with pitting and peeling of the sealant layer (see pic), although there is no evidence of leakage. I’m looking for options for resealing, preferably something that will last for quite a few years.

[MitchellMc]

Welcome to the Bunnings Workshop community @BrianK. It's wonderful to have you join us, and many thanks for your question about sealing a pond.

Seven to ten years is around about the lifespan of the Crommelins Pond Sealer. If your pond is in-ground, then you need to apply two coats of Crommelins Dampstop to the bottom and sides prior to the pond sealer. If it's on the ground, I'd suggest painting the bottom. This prevents moisture in the ground from pushing the sealer off the concrete, which will be seen as bubbling. If ground moisture is the reason for the product delaminating and you hadn't used the Dampstop, then you might see a longer span of time once you've re-applied.

I'm unaware of other pond sealing or waterproofing products that would outlast the Pond Sealer.

Please let me know if you have any questions.

Mitchell
 

[BrianK]

Thanks Mitchell - appreciate you thoughts.

I'm thinking I will have to find a way of removing the old coating before putting another treatment on - otherwise anything I put over the top might fail if bits of the old .coating release.

[EricL]

Hi @BrianK 

I agree with you, it will be necessary to remove the old coating and give the concrete a bit of a polish. Once you've removed all of the old coating you should be able to examine the base much better and you'll be able to tell if there is any structural damage.

If you need further assistance, please let us know.

Eric