Waterproofing concrete pond: plaster, fiberglass, painted-on rubber?

[zeuspaul]

Rapid Set has is similar to portland cement products. It has a few advantages. It has more strength, sets faster, shrinks less and sticks better.

 

[moocowman]

Rapid Set is a brand that has a whole line of cementitious products; concrete, stucco, mortar, grout... I think their concrete mix has aggregate larger than sand. So, it can't be spread smooth as a plaster. They do have a waterproofing mortar that you might be able to use as a plaster.

 

[GBBUDD]

Untill you get into extremely expensive admixtures when it comes to cements . The longer it takes to cure generaly the longer it will last

 

[PNDFARY]

Actually, plaster ratios vary. You can make plaster anywhere from 1:2 to 1:3. So, what you're using for concrete could really be called plaster. When you lay it down thick, you call it concrete. When you spread it on a wall, you call it stucco. When you fill gaps with it, you call it grout. Traditional concrete usually has some larger aggregate in addition to sand, but coarse sand is a suitable substitute for gravel in a fish pond. You're not pouring a driveway or a house foundation.

My mom built 3 ponds just as you are doing; chicken wire and cement/sand. No plaster, no liner. The one she has at her current house is 5000 gallons, built about 10 years ago, never had a problem. This is how ponds/pools and fountains have been built for hundreds (maybe thousands) of years. I really shouldn't have bothered with the plaster in my pond. I tiled the upper 12" of the pond. Once the algae turns the walls green-black, you cant see the plaster anyway.

If you decide to plaster... You can get black and brown pigments from Home Depot or Lowes, usually sold as Quickrete liquid cement color. If you want other colors, Amazon sells concrete pigment. Cement is usually gray. So, you'll be mixing color with gray. You can get brighter colors by using white cement. White portland cement is available at some Lowes locations in my area, but Home Depot doesn't offer white portland at all. As for consistency, add as much water as you think you need to get a consistency where you can spread it on without it sagging or falling off. I know there's a science to water ratios, but again, you're not building a swimming pool for the Ritz Carlton. In reality, you're supposed to add that specific amount of water, then use "superplasticizer" (aka "water reducer") to make it more runny. Forget that stuff. You should apply it to concrete that's damp. Mist water from your garden hose to dampen the concrete. Plaster has a hard time hanging onto dry concrete, especially vertical surfaces. Once you're done applying the plaster, fill the pond right away. Plaster cures underwater.

You’re my hero. Thanks for all this info. I decided a few days ago that I didn’t need plasticizer since I’m not building a road or an 80-story building.

 

[zeuspaul]

Portland cement concrete tends to shrink and crack excessively. It is susceptible to attack by prevalent chemicals such as sulfates. These limitations cause the concrete to become unsightly and less durable, increasing the possibility for structural problems.

Rapid Set cement based products are low shrink and the risk of cracking is greatly reduced. The products are also more resistant to sulfate attack. Rapid Set cement helps achieve stronger and more durable results on your projects.

Rapid Set vs Portland | CTS Cement

www.ctscement.com

 

[PNDFARY]

Portland cement concrete tends to shrink and crack excessively. It is susceptible to attack by prevalent chemicals such as sulfates. These limitations cause the concrete to become unsightly and less durable, increasing the possibility for structural problems.

Rapid Set cement based products are low shrink and the risk of cracking is greatly reduced. The products are also more resistant to sulfate attack. Rapid Set cement helps achieve stronger and more durable results on your projects.

Rapid Set vs Portland | CTS Cement

www.ctscement.com

Thank you for this info. I appreciate you.