Would this work to reduce CH without draining?

[aztodd]

It seems like there must be some device out there that could remove calcium from my water in my pool without costing an arm and leg. I just really don't want to have to drain my pool since every other aspect of my water is fine, but my calcium hardness is above 700 now and the scaling on my swg is difficult to manage unless I babysit my CSI which I just don't have time to do.

https://www.amazon.com/Aqua-Pure-AP430SS-Water-System-Protector/dp/B000NKETXQ/ Would this or something like it work to remove calcium from my pool water if I installed it in my pool equipment? What even does this do exactly? I cannot tell how it is working and if it could feasibly filter calcium out of a 13,000 gallon pool.

I'm open to out of the box ideas here, so throw them out to me. Thanks

 

[mknauss]

No.
You have two reasonable choices. Drain and replace with lower CH water, or use a Reverse Osmosis process that will remove the dissolved solids in your pool water.

You show using softened water for make up water. How did the CH rise to that level?

 

[ajw22]

No, the polyphospahates that are the active ingredient in the device will be neutralized by the chlorine in pool water.

In addition that device can handle a flow rate of 10 GPM. It will take 21 hours to flow your pool water through at that rate and then the water will still have high CH.

 

[aztodd]

You show using softened water for make up water. How did the CH rise to that level?

That is a good question, I am not entirely sure. I need to test my fill water again and see what's going on. Regardless of how it happened though, it is my current reality.

Okay so this device or anything like it will not work. Got it. I've looked into reverse osmosis before, but that is a very expensive endeavor.

I am not a chemist, but it just seemed like there must be something out there that could remove calcium from water without too much complexity. Maybe it does exist, just not at the scale of a swimming pool.

 

[mknauss]

out there that could remove calcium from water without too much complexity.

That is a water softener.

If there was an easy way to remove calcium from our fill water, we would be pushing it to no end. Just does not exist.

 

[aztodd]

the polyphospahates that are the active ingredient in the device will be neutralized by the chlorine in pool water

Does the calcium bind to the polyphosphates in this cartridge? Just wondering if I ran this in the winter and kept my chlorine at basically zero would it make any difference.

I understand this is not designed for pools, so just think of this as I thought experiment. Why would this not work, or does it not actually remove calcium from water in the first place?

 

[ajw22]

Does the calcium bind to the polyphosphates in this cartridge? Just wondering if I ran this in the winter and kept my chlorine at basically zero would it make any difference.

I understand this is not designed for pools, so just think of this as I thought experiment. Why would this not work, or does it not actually remove calcium from water in the first place?

Feel free to do the science experiment and report back the results.

 

[JamesW]

Calcium does bond to phosphate and chlorine does not affect phosphate.

However, you might only remove a few grams of calcium with the device.

You could actually throw a bunch of TSP (trisodium phosphate) into the water and precipitate the calcium out as calcium phosphate.

This used to be done to reduce calcium levels.

However, it has been found to create many more problems than it solves.

You do not want to add phosphate to your pool.

You can drain and refill if it's safe to do so or you can get a reverse osmosis treatment.

 

[JamesW]

It takes about 12 lbs of calcium chloride to increase the calcium hardness by 100 ppm in a 13,000 gallon pool.

 

[JamesW]

Ask the manufacturer how much calcium the device can remove from your pool and if they will provide a written guarantee of performance.

 

[aztodd]

Calcium does bond to phosphate and chlorine does not affect phosphate.

However, you might only remove a few grams of calcium with the device.

You could actually throw a bunch of TSP (trisodium phosphate) into the water and precipitate the calcium out as calcium phosphate.

This used to be done to reduce calcium levels.

However, it has been found to create many more problems than it solves.

You do not want to add phosphate to your pool.

You can drain and refill if it's safe to do so or you can get a reverse osmosis treatment.

I appreciate your insights here, very helpful!

 

[Dirk]

That is a good question, I am not entirely sure. I need to test my fill water again and see what's going on. Regardless of how it happened though, it is my current reality.

I fill my pool with soft water and still got some CH rise, though it took several years. It got over 500 last fall so I did a partial exchange. That and California's weather this winter brought it back down to about 325. I have some theories:

(1) Even though my softened water tests at CH=zero, I suspect that is the best the test can do and there is actually some CH not registering with the test, so some CH is still getting past my softener.

(2) As the softener progresses through it's regeneration cycle (every few days or so), I suspect CH in the softener output increases some amount the closer the cycle gets to the end, just before regenerating. In other words, if my regeneration cycle happens every four days, the water is getting a little harder each successive day, until it regen's and then starts over at CH-zero (or near-zero). So it's likely there is always some amount of CH going into the pool.

(3) If you have any sort of auto-filler (as I do), then your pool can top itself off at any time of the day or night. During the softener's regeneration cycle, the softener goes into bypass mode. So it no longer outputs soft water, but rather passes the hard water from your water company. Which means if the auto-filler happens to engage while the softener is regenerating, your auto-filler will be pumping hard-water into your pool.

I solved for #3 by using a motorized valve and my pool automation controller to shut off the auto-filler supply line during my softener's regeneration cycle. I won't know for several years if that will make a difference.