A long lesson on concrete.

[JD Lloyd]

I am in the process of building a new concrete pond. The folks doing the concrete work are a large swimming pool contractor and they will use shotcrete. The walls and bottom will be 8 inches thick with # 3 rebar in a 12 inch grid. when I started trying to figure out what kind of sealer would be best I have gotten advice that is all over the place. Yesterday I was told that a product called UGL DRYLOK EXTREME would be the way to go. This product is a paint.......Please advise......JD Lloyd

[RichToyBox]

Good concrete, well cured needs nothing as a sealer. Many on here have used an admixture called Xypex which will, supposedly, create a crystal structure through the concrete blocking any pores that water could find its way through. Be sure that your plumbing is pond plumbing and not swimming pool plumbing as there is a significant difference in the power of the pumps, and the amount of debris to remove from the pond. The only coating that I would use in a pond is the same one used by the swimming pool construction, which is well tried and true to hold water. Many of the paint on have a high frequency of failures, pealing off. Concrete really does not tolerate coatings very well. Most are film forming which allows vapor pressure to build up in the concrete and put them off.

Pool contractors doing shotcrete tend to leave the shotcrete too rough for the finish surface on a pond. Get them to go the extra mile and give the concrete a finish more like a floor.

[Mr. C]

Thanks for this! Just posted my first thread... and it now looks like a stupid question because it's all about concrete. I just want to use enough to seal up the base of my expanded waterfall and tie together (fill in the gaps) of the matching, large stone slabs ringing the pond edge. From what I've read, Rich, I won't have all that much water in contact with concrete/cement/mortar. And perhaps therein lies the question: What should I use to do this? Enlarging the base of the waterfall, along with placing giant stone slabs, has created a nagging water loss that I'd like to "seal" off without rebuilding waterfall. That must be done... and I think the "mortared" stone slabs can create a nice edge / waterline so that the liner is hidden. I saw somewhere online where a guy (seemed reputable) came up with a mixture of concrete so it wouldn't need to be cured?

[drterrie]

Hello everyone! My very first post (except I think I posted a welcome).
I have concrete ponds in my urban garden. Three ponds with waterfalls ending in a below ground basin where the pump is. One of the ponds still seems to have a leak at about 2" from the top. I determined this because it stops leaking at that level. I saw in another thread to use Permaflex over the cement. We tried thoroseal (part of it peeled off - not much). A few questions:
1. Is permaflex a waterproofer?
2. Is it okay for the fish?
3. Can we paint it - eventually?
4. It seems (if I am reading it correctly) that it is a primer, so we don't need to prep the surface except, of course to clean it up. Is that right?

Thanks for all your help and wisdom - I am on such a huge learning curve!!!

Here's a pic: https://www.dropbox.com/s/sd148j4pah..._0250.MOV?dl=1

Terrie

[icu2]

Hi Terrie,
To get the most help with your specific problem you should probably start
a new thread here in the Construction forum and you could just copy and
paste your post there. Very nice ponds too!

[Samm]

I'm researching pond-safe coatings for concrete ponds and have seen videos on Pond Shield and Drizoro Maxseal Flex and Maxplug. Are you familiar with these products and do you have a recommendation for the best way to go with the coating now that I am finishing the concrete and mortaring phase of my pond remodel? Steve from Koiphen said he likes the Xypex admixture best. I've never used a coating over my previous concrete ponds but never raised Koi, just goldfish. I want to make my new Koi pond the best it can be so should I go with the coating? It would also be nice to try the different colors that come with the coatings. I'm wondering if one color looks better than another under the water. Has there been a color preference among Koi pond builders, I wonder.

[Samm]

Good to know that well-cured concrete doesn't need a sealer for my project on a tight budget, which makes me want to ask what what technique makes for "well-cured?" I'll google or You Tube it. I just mix my concrete and mortar with a shovel one 60lb. bag at a time in the wheelbarrow and try to measure the water as the directions on the bag say. On a lot of my pond, however, I used concrete blocks, with the holes or cells filled with concrete since I needed two walls of the pond to be a retaining wall against the hillside, only about 4 feet high though. I spread mortar over the concrete blocks very thin since it's straight up vertical. I've never used concrete blocks covered with mortar like this since my previous concrete ponds were smaller with no steep sides to stick concrete too. Since I'm new at larger Koi pond building, having only done smaller goldfish ponds that did fine enough for the goldfish to seem happy, I'm wondering if my amateurish first attempt at a deeper larger pond using concrete blocks covered with mortar will even work. It's only about 10'L x 5W'x4'deep but I figure it should work for goldfish and baby Koi as I learn how to test water quality and build larger effective filters while I am building next to it slightly downstream a larger pond about 30'x10'x3 to 6 feet deep where I plan to make wooden forms to pour the concrete into instead of concrete blocks, as in a perimeter foundation I did for my home with a concrete truck and pumper to fill in the forms. So I might combine the pour of the pond with the pour of a small guest house foundation next to the pond in which case I might order a cement truck to do it all at once.
I suppose I'll soon find out if my smaller first phase learner-pond with mortar spread over concrete blocks will work but my question is--would it help to invest in the pond sealer painted over the over the mortar? I suppose it would be worth the effort for a better seal if the mortar sticks okay to the blocks. Pretty amateurish as I attempt to upgrade from small goldfish ponds to larger Koi ponding, but I want to get some kind of pond started relatively fast for me and learn water-quality monitoring as well as doing a few kinds of filters in the starter pond, while taking my time on the larger Koi pond and getting that right with all the great support here at Koiphen community and seeing how the first phase small pond goes.
I noticed the wide variety of colors the Pond Shield comes in, as well as just clear. Does anybody have an opinion on what effect on the overall look of the pond has depending on what color the sealer is? They have black, green, light and dark blue, tan, grey, and clear I think. I suppose it would be fun to try all the colors, although the Pond Shield is almost $300 per 1.5 gallon can.
When I get a picture of my new first phase pond remodel in progress I'll post it. Looks pretty amateurish so far compared to the builds I've seen posted at Koiphen but I need to start somewhere and I was already half-way into it before I found this site to learn from.

[batman]

All concrete eventually cracks and the coatings/sealer are insurance to seal hairline cracks and prevent further damage from internal seepage. It definately matters much less if you live in a mild climate such as yours. Small seepage in hairline cracks expands when frozen and repeated many cycles this is the damage you see in concrete in cold climates.

Edit- I see where you are using block. Yes a sealer will be needed.

[Shalmaneser]

I'm designing a new pond. It's an expansion on an existing 14' l x 3' w x 2' h filled cinder block tank. It's part of an existing deck that ranges from 2' off the ground to 4'. Most of my designs are 14'x12' filled cinder block. The question: How high can I take a these dimensions above ground? 3' would be minimum to be flush to deck. Higher would be better to add windows,

[icu2]

I'm designing a new pond. It's an expansion on an existing 14' l x 3' w x 2' h filled cinder block tank. It's part of an existing deck that ranges from 2' off the ground to 4'. Most of my designs are 14'x12' filled cinder block. The question: How high can I take a these dimensions above ground? 3' would be minimum to be flush to deck. Higher would be better to add windows,

Probably best if you create a new thread in the Construction Forum and include a couple of pictures for experts to see exactly
what you're describing. Good luck with the new pond