Lowering Calcium Hardness & Alkalinity

[bxcrwlly]

Just completed a no-drain acid treatment on the pool to remove hydration stains. Now trying to balance pool. All going well except Calcium Hardness and Alkalinity. PH was 7.4 with Alk at 175, so I dropped PH to 7.0. Any idea how long it takes Alk to drop with PH at 7.0? Out of the faucet, CH is 250. Mine was at 500. After a couple of partial drains approximately 40% last Thursday and 30% on Friday, my CH is now at 425 and of course my local county water department is laughing all the way to the bank. The Pool Calc(Smart Phone Version) is telling me with a source of 250 and a goal of 300, I need to drain 71% of my water. After spending $$$ on start up products to balance pool, I really don't want to flush more money down the drain. Looking for insight on another approach to lower CH to 300. I went to pool store to purchase salt. I did the no-no and had them test the water. I have a Taylor K2006 so I wanted to compare. We were spot on with FC, CC, PH. They showed my CH at 440 when I tested 425 and Alk at 190 when I tested at 175. Interestingly enough, I was trying to get CYA to 70 and my kit showed 35. Theirs showed 60. That was a shocker.

Anyway, while talking to owner, she said she thought CH would go down as water temp came up. My water temp is currently at 64 deg.

As always, any help is appreciated.

 

[JasonLion]

There aren't any easy ways to lower CH. Your only choices are water replacement and (in limited areas) a RO treatment company.

CH levels don't change with temperature.

CH at 440 and 425 are the same reading within the precision of the tests. The same thing with TA at 190 and 175. The CYA result is actually different, and bears investigation. One thing to keep in mind is that the CYA test can give false low results if the water is cold and you don't let it come up to room temperature before doing the test.

 

[duraleigh]

Last Summer, I did an informal survey of water rates among some geographically selected members. The HIGHEST water rate was a bit less than $5.00 per 1,000 gallons.

If you are anywhere near that, you should be able to replace about 70% of your water for $35.00 or so.

 

[bxcrwlly]

Thanks guys. One other question. In another post I mentioned I was using a sequestrant on a weekly basis and was questioned as to why. At the pool store, a sequestrant level test was performed. My results were (2). The recommendation was to keep it around 10-12. Do you agree or is this an unnecessary expense?

 

[JasonLion]

There is no point in using sequestrant unless you know you have metal issues. On the other hand, if you do know that you have metal issues, using sequestrant is often essential. What an appropriate sequestrant level is depends on the metal level in the water. There isn't any single level that works in all situations.

 

[duraleigh]

The chances of appreciable metals dissolved in municipal water is pretty small. You should test for it, though

 

[bxcrwlly]

Jason..thanks. I do have a heater on the pool so I worry about copper entering the water. Should this be a concern? Also regarding my original post, on CH reducer(s). I get the water draining process but stumbled onto a product called CalTreat. Mixed reviews as to its effectiveness. Seems to bind calcium for filtering from the pool. Any input regarding the product?

 

[Boland01]

As some of the other members dhave done, I have also set up a roof drain system to transfer the rainwater to my pool when it rains. I have two separate feed drains and can increase the water in my pool by 2-3 inches with under an inch of rain at a time.
It's just PVC layflat hose connected to a coupler that goes over my drain spout. On the pool side end of the PVC hose I have mesh bags to catch any 1/8" or larger derbris. My pool is 28,000 gallons. Since switching over to the rainwater system I've only had to add tap water once or twice in a year.

Where this might benefit you in the long run is the rainwater should have close to zero CH. Once you get your CH in check this can help you keep it there. Best of all the rainwater is free.

 

[JasonLion]

Very few people have tried CalTreat. All of the reports I saw were negative, but there aren't really enough of them to draw a strong conclusion. When it first came out we tried to figure out how it worked but didn't get anywhere.

 

[bxcrwlly]

Here's an interesting twist. I checked our faucet water that's connected to our water conditioner system. The CH readings were between 0 and 25. We're hooked up and refilling only 32% of the pool using that source vs. 71% from the outdoor bibs. Only downfall is time to refill and possibly salt in the water conditioner.

 

[bxcrwlly]

Completed the fill today. Filled from 2p to 10p on Sunday resuming again Monday 6a.m. Completed around 3p.m. Monday. Running hose from Garden Tub faucet to pool to obtain "conditioned water." Had comparable pressure to outside bibs. Had to "regen" my conditioner 4 times, at 1.5 hrs. ea. to complete the fill. When completed my CH was 250. Added salt, PH adjusted to 7.0 as TA was at 175. Using 10.5% liquid chlorine to bring level to 5ppm until SWG can catch up. Will test CYA on Tuesday. I'll remember to let test water adjust to "room temp" before testing...another good TFP pool tip. So far all is looking good. Thanks Boland01 for the rainwater suggestion. I'm looking into setting something up similar to what you described. Jason/Dave S...thanks for your feedback on metals and CH.

 

[bxcrwlly]

Any ideas on how long it will take to adjust Alkalinity to 70? Going on a week adjusting PH to 7.0 with Ak now at 150.

 

[257WbyMag]

Any ideas on how long it will take to adjust Alkalinity to 70? Going on a week adjusting PH to 7.0 with Ak now at 150.

It can take weeks to get the TA down to where you want it to be. Aeration is an important part of the process and does much to determine the rate at which things progress. Patience and persistence is caled for.

 

[bxcrwlly]

Thanks 257WbyMag....Paitience is typlically not my strong suite. I only have a water feature flowing from the spa to the pool for aeration. Perhaps I should invest in a fountain or two to expedite the process? Other suggestions?

 

[Richard320]

Thanks 257WbyMag....Paitience is typlically not my strong suite. I only have a water feature flowing from the spa to the pool for aeration. Perhaps I should invest in a fountain or two to expedite the process? Other suggestions?

If you have an air pump for the spa, turn it on. And divert as much flow to the spa as possible. The more churning and frothing you see, the better.

 

[bxcrwlly]

Richard320...great suggestion. Will do. Thanks!