Xypex issues

[koilaria]

Hello,

So a bit of an unfortunate story.

I have built a 12' x4' x 4' pond, roughly 1200 gallons above ground with poured concrete slab and CMU block. Reinforced with rebar.

We filled the block with concrete and then I used xypex concentrate + megamix 1 on the inside to waterproof. I did this back in March.

Pond seemed to be waterproof and would fill up with rain when it rained, and I in the meantime built the filter, put a stone veneer on the outside and installed a 4' x2' piece of glass in the front.

I filled up the pond late may when the plumbing was complete. Unfortunately its not waterproof at all. The window and plumbing has no leaks but the sides of the pond are visibly wet and I have been losing 50-100 gallons of water a day.

I talked with the xypex rep and he told me to wait 30 days since the xypex crystals activate with water and it may take some time. It has been 21 days now and I see no improvement, I'm still losing a huge amount of water every day.

I talked with the xypex rep again and he really wasn't sure what to do. He talked with some of his colleagues and they reccomend removing the layer of megamix I added and restarting.

I feel so defeated. I really have no skills to remove this megamix, it is stuck to the walls and I have no idea how I could remove it. I just want it to be waterproof. I used xypex because it seemed to be a reliable solution many people had success with but it is clearly not waterproof enough right now.

Im not sure if anyone has any advice. Im tempted to try to find a pool company that could maybe figure something out. But I'm not sure what to do.

[stevek]

You could add a standard rubber liner or else get a custom drop in liner. Then add a coping stone on top to hold the liner in place. Many ponds are built like this by design, so it will look great ! Don't get discouraged !

[aquaholic]

Amateur fish forum here so don't expect professional advice even though it's well intended.

How much clay is in your soil? Do you think the blockwork has moved with soil expansion from moisture?

How thick is your Xypex Megamix 1 coat? Was it professionally applied?
Xypex crystals need to expand into voids to seal so your megamix 1 coat needs to be 20 - 40mm thick to work effectively I suspect. Can you not apply a second megamix 1 coat over the first? Having a different colour coatvwould allow you to visually confirm no gaps.

If you go for something else, make sure this can be waterproofed in the future without having to strip it off.

If your blockwork could be moving then a rubber liner, fiberglass or polyurathane spray would be the best options. Blockwork leaks are very hard to locate.

[JohnDoe123456]

This is not professional advice.

I would empty the pond, if there are fish inside get a frame pool (as large as you can fit) then pump water from your leaking pond into it and transfer the fish when you see fit then add air stones (the pool also saves on water). After you've emptied the pool just add another layer of product on the inside of your pool. Pond safe bituminous/liquid rubber coatings (don't get ones not explicitly for this purpose), most epoxies, acrylics, any number of specialty resins, other more efficacious cement mixes just for pool use. There are dozens of classes of products and thousands of different ones but I don't know what available to you.

Either way if my understanding is correct and you've got a finished concrete pond that was sealed with a product that doesn't work then I'd just add another layer of another product that does work. No need to break off the cement. For the glass you can seal using modified silicone/polymer glue if you've got any leaks there.

[koilaria]

Hi all,

Thanks for the advice.

I spent some time with the xypex rep, and he was telling me that I will need to remove the entire megamaix I layer and redo it all. That seemed like a nightmare, so I asked around with local pool builders and sealant dealers. A contractor I talked to said that he never uses megamix, for everything he just uses 3 coats of concentrate and then Xypex gamma cure to cure it. He reccomended that I just apply 3 coats of concentrate over what I did, even though the "megamix" is a "bond breaker" meaning that given it has the xycrilic in it, it will stop the formation of crystals.

I did this and waited 2 weeks, and filled the pond. Initially it looked like it was perfect, no leaks. But now, 4 days after, its leaking. Better than before, and slower, but water is getting out.

Unfortunately, I just cant seem to get the xypex to work. The concentrate is adhered on there well, so I think I will probably do a pond armor coating over that and give up on the xypex for now.

[aquaholic]

That's not a good update.
Perhaps you need to wait the full 30 days for crystalline expansion?
If XYPEX isn't working, I suspect your blockwork is moving - creating more cracks.

Whatever waterproofing product you try next, make sure it can be coated over in future without having to remove it. So future repairs are simple.

[koilaria]

That's not a good update.
Perhaps you need to wait the full 30 days for crystalline expansion?
If XYPEX isn't working, I suspect your blockwork is moving - creating more cracks.

Whatever waterproofing product you try next, make sure it can be coated over in future without having to remove it. So future repairs are simple.

Thanks. I am really doubtful it is the blockwork moving... the blockwork is solid, mortared, filled in block with rebar horizontal and vertical every single cell. There are no cracks whatsoever in the xypex.

Will waiting make a difference? If I dont need to apply the pond shield, then that would be most ideal. But I waited 30 days last time without change...

It also seems that the descriptions of xypex I have seen all mention it is waterproof from the start, not leaking and then 3 weeks later stops. Not sure if your experience was different?