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MAV AquaDoc Pool Calcium Hardness Increaser - 5lb - Fast-Dissolving Calcium Chloride for Swimming Pools - Made in The USA

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$27.99

$ 13 .99 $13.99

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About this item

  • Support Calcium Hardness Levels - AquaDoc Calcium Hardness Increaser for swimming pools helps raise low calcium levels in swimming pools, supporting optimal water balance and long-term pool care.
  • Fast-Dissolving Calcium Chloride - Made with high-quality calcium chloride flakes, this pool hardness increaser dissolves quickly and is compatible with all pool types, including chlorine and saltwater systems.
  • Easy to Use - Add the pool calcium increaser directly to pool water while the circulation system is running. Ready to swim in just 15 minutes! Helps maintain calcium hardness between 200-400 ppm for balanced water chemistry.
  • Compatible with All Pool Types - Ideal for both inground and above-ground pools, AquaDoc is trusted by pool owners across the country for reliable and consistent results.
  • Made in the USA - AquaDoc pool chemicals are proudly made in the USA and manufactured to high quality standards. Dependable solutions to support your pool’s water balance.



Product Description

AquaDoc Pool Calcium Hardness Increaser

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Pool Calcium Increaser For Balanced Water Chemistry

AquaDoc Pool Calcium Increaser raises calcium hardness to prevent corrosion and surface damage. This fast-acting calcium chloride formula protects pool equipment, tile, and plaster. Safe for all pool types, it helps maintain ideal hardness levels between 200–400 ppm. Use regularly to extend the life of your pool and maintain balanced water chemistry for safer, smoother swimming.


Jennifer Howard
Reviewed in the United States on June 1, 2025
Great product brand and it is 5 lbs. Very easy to use in a pool and dissolves very quickly. This product works as described and I would highly recomend this product.
D Smith
Reviewed in the United States on May 9, 2025
Not sure what to say. Like the title says. It's calcium and it dissolved quickly. Per the instructions, this bag would only raise my pool's hardness level by about 10, which isn't nearly enough when opening a pool after partially draining it in the fall. Having all the fresh rainwater really drops the hardness level, so it typically requires quite a bit of calcium to get it back up. This is a good batch to use if you have a smaller pool or just need to raise it a little bit more.It was very easy to use. Just tear open the bag and pour into the pool. I walked around and poured it out in the deep end. I used a brush to push the little bit at the bottom that didn't dissolve right away. It instantly dissolved with the brush.
LPZ
Reviewed in the United States on May 9, 2025
I have a 13k gallon pool, and after opening my pool for the year I noticed the calcium hardness level was a bit low. I did not want to waste time going to the pool store and it was same day delivery so I figured - why not!? I calculated approximately half the bag would work for my situation. I decided to give this a try and it worked perfectly.The product came in a resealable 5 pound bag. It’s made in the USA. The chemical dissolved quickly without leaving any residue, and I followed the instructions to avoid mixing it with other chemicals (pump running on high). I measured out what I needed based on my pool’s levels, and within a couple of hours, I saw results. My calcium hardness went from 170 ppm to a little over 200 ppm. No issues.
P. Killion
Reviewed in the United States on May 8, 2025
Pure calcium chloride, the best way to increase your calcium hardness levels to meet LSI pool chemistry requirements. The flakes dissolve easily and are pure, and the price value is currently one of the best on Amazon for the quantity, and comes from a reputable brand to boot.Do note that calcium chloride does undergo a chemical reaction when put into water, as such, you will definitely want to first get a large bucket and fill part way with water, then add the flakes to that to let dissolve (always add the chemical to water, not the other way around, so the water doesn't splash the chemical up towards yourself). You will notice the bucket gets very hot due to the reaction, which is precisely why you use the bucket as it can damage pool plaster and liners.So minor precautions when using, but very simple and easy to do, and of course Amazon has the best value around on this stuff it seems.
Nikki
Reviewed in the United States on May 6, 2025
I am new to taking care of pools and have tried out several products in my journey to get it right. I am a big fan of the AquaDoc products so far so I wanted to try this calcium hardness increaser when my testing revealed the calcium hardness was low in my pool. First, this is made in the USA which is very important to me. The product comes in a resealable 5lb bag package. I measured the product (using a scale) based on how much I needed to increase. The flakes dissolve quickly and did not leave a residue. I followed the instructions not to add at the same time as a product that increases/changes pH or alkalinity. I adjust my chlorine and baking soda on Wednesday and take care of calcium hardness on Thursday. My pool is always ready to go on Saturday! This product works within a couple of hours so you're in luck if you need results quickly. Great product but price is a little high ($16.99 for 5lbs which is $3.40/lb vs leading competitor $8.74 for 4 lbs which is $2.20/lb).
Yervant Parnagian Jr
Reviewed in the United States on May 27, 2025
Worked great for my spa. Used warm water to dissolve and put it in the spa. Brought up my hardness levels. Hardness level has been consistent. Also, no need to adjust my PH too.
Meatkaka
Reviewed in the United States on May 22, 2025
I live in Florida where the heat and rain can really mess with pool chemistry, and I noticed my calcium hardness levels were dropping. I ordered this AquaDoc Calcium Hardness Increaser and was super impressed with how easy it was to use.The instructions were clear—just add it directly to the pool while the pump is running. It dissolved quickly with no clumping or residue, and I was able to swim again in about 15 minutes. I tested the water the next day and my calcium levels were right where they needed to be (between 200–400 ppm). It helped balance everything out and gave me peace of mind knowing my pool surfaces are protected from corrosion.I also love that it’s made in the USA and works with both chlorine and saltwater systems. Definitely a must-have for any pool owner looking to keep their water balanced and their equipment in good shape.Highly recommend!
jamie y
Reviewed in the United States on May 19, 2025
Works great! Good directions! Wish the bag was resealable!Decent price! Dissolves pretty quickly! Does the job well!
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