Brand new pool owner = new to BBB method

[stslimited84]

I used the pool calculator link and its telling me I need to add 237 lbs to bring the calcium level up from 200 to 300 ppm. Is that right? Sure seems like a lot of calcium chloride to add.

[BigDave]

I think you've got some extra digits somewhere. 237 lbs sounds w-a-y high.

[PoolDoc]

One of the reasons I'm not in love with the pool calculator is that it tends to encourage people toward a 'fix it in one dose' approach to chemistry. This was a BAD idea, when pool stores pioneered that approach, and it's a BAD idea now.

There IS an exception: low chlorine should be fixed in one dose, and usually, more is better. (More as in 3x too much, not 50x too much!)

For everything else, it's much, much better --- in PRACTICE --- to dose, test, and re-dose if needed. For your 25-30,000 gallon pool, you are around 1/5 of a million pounds of water. So, if you add 1 lb of CYA, your CYA level will increase by 4 - 5 ppm. Calcium chloride dihydrate ends up being about 60% 'active' with respect to CH test results, so 1 # of Calc chloride will add 2 - 3 ppm calcium hardness.

So, if you wanted to increase your CH by 60 ppm, you'd need to add 20+ lbs of calcium chloride. But DO NOT DO THIS! As mentioned above, it's a generally bad idea. But, in a pool with a chemistry approaching calcium carbonate saturation, ANY large addition of pH+, alkalinity+ or calcium+ will tend to precipitate a cloud of calcium carbonate.

What's the solution? If you need to take a pool to saturation -- and you probably don't -- SMALL repeated doses are a much, MUCH better way to do it. So, instead of adding 20+ lbs, add 5 -10 lbs and then retest.

[stslimited84]

I think you've got some extra digits somewhere. 237 lbs sounds w-a-y high.

Yeah you're right, I had an extra zero on the calculator. I knew that figure was not correct, good catch.

One of the reasons I'm not in love with the pool calculator is that it tends to encourage people toward a 'fix it in one dose' approach to chemistry. This was a BAD idea, when pool stores pioneered that approach, and it's a BAD idea now.

There IS an exception: low chlorine should be fixed in one dose, and usually, more is better. (More as in 3x too much, not 50x too much!)

For everything else, it's much, much better --- in PRACTICE --- to dose, test, and re-dose if needed. For your 25-30,000 gallon pool, you are around 1/5 of a million pounds of water. So, if you add 1 lb of CYA, your CYA level will increase by 4 - 5 ppm. Calcium chloride dihydrate ends up being about 60% 'active' with respect to CH test results, so 1 # of Calc chloride will add 2 - 3 ppm calcium hardness.

So, if you wanted to increase your CH by 60 ppm, you'd need to add 20+ lbs of calcium chloride. But DO NOT DO THIS! As mentioned above, it's a generally bad idea. But, in a pool with a chemistry approaching calcium carbonate saturation, ANY large addition of pH+, alkalinity+ or calcium+ will tend to precipitate a cloud of calcium carbonate.

What's the solution? If you need to take a pool to saturation -- and you probably don't -- SMALL repeated doses are a much, MUCH better way to do it. So, instead of adding 20+ lbs, add 5 -10 lbs and then retest.

Thanks for the replies. So Doc, let me ask you. How do I know what the saturation level is for the pool and at what level to stop? I want to make sure I get the calcium level where it so its all set when it comes time to close the pool in a month or so, b/c if ive read correctly, having a calcium level to low in a plaster pool can cause damage to the pool due to the water drawing calcium from the plaster.

I 100% agree with your slow dose and retest method. Have been using it since I started BBB.

[stslimited84]

Just to verify, would the best way to add the calcium be via the sock method?

also, sadly it will be time to close the pool in a few weeks...I will be having a pool company take care of the closing in regards to the equipment (blowing out the lines, cleaning the filter, etc), but Ill be handling the chemical aspect.

What do I need to do to close the pool chemically?

Thank you kindly

[stslimited84]

i was able to locate some peladow as suggested. How should I add it to the pool? sock method or add via the skimmer into the filter?

[stslimited84]

i was able to locate some peladow as suggested. How should I add it to the pool? sock method or add via the skimmer into the filter?

anybody?

bueler? bueler?