No CYA in pool, redux

[StevenHB]

Thanks for your welcome. I've recommended this site to two friends who bought houses with pools in the last year. I couldn't say enough about how much I've learned here, at PoolSolutions, and from the various linked materials.

Sorry about confusing the posts - I actually thought that it made sense in the context of the other poster's question since Ben created a framework in his response but didn't fill it in. This is the first pool chemistry problem I've had.

Anyway, is there a reason that you and Ben suggested that I use liquid chlorine instead of granulated? I have *lots* of granulated.

[PoolDoc]

Anyway, is there a reason that you and Ben suggested that I use liquid chlorine instead of granulated? I have *lots* of granulated.

Yeah. Bleach is less complicated. If you have cal hypo, that will work well if you have a sand filter. With a DE or cartridge filter, it's a little more complicated.

If you have dichlor, we need to work out how high you want your CYA to be, and make sure we stop using dichlor before overshoot.

So do this:
1. Post your pool info (gallons, surface type, make/model of your pump/filter, other equipment) in your signature (Link in MY signature)
2. Tell me what kind of granular (dichlor or cal hypo) you have, and how much.

And, then we can go from there.

[StevenHB]

Sig updated with more information than you need (I uploaded all details a long time ago to Google Docs so I could find it anywhere/anytime).

I have ~60 lbs of cal hypo (I usually buy 50 or 100 lbs once a year).

I should probably also tell you that I added 3 lbs of granulated CYA last night.

[PoolDoc]

added 3 lbs of granulated CYA last night.

Hm-mmh. Via your skimmer?

Ok -- like this:

1. No more CYA, till you can hold a residual overnight, and your CC is 1.0 ppm or less.
2. FIVE gallons of plain 6% bleach each EVENING through Thursday PM
3. Friday, clean your filter -- you have to get any remaining CYA OUT of the filter.
4. After the filter is clean, make 1,000% sure that there is no trichlor, no ionizer, no NOTHING except pipe and pump between the skimmer and the filter. Note your clean filter pressure.
5. Dose with 5 lbs (6 cups) of cal hypo added SLOWLY to the skimmer. Add the first cup, and wait 30 minutes to see if you forgot something. If there's still CYA in the filter, it will sound like you are cooking popcorn in it -- when the CYA + cal hypo particles DETONATE! Usually, this doesn't damage the filter, but it's MUCH better to avoid this.
6. Repeat EACH evening. Clean the filter by opening and washing it out, when the pressure has gone up 10 psi.

Several comments:

=> If you haven't already raised the pH, per instructions above wait to do so, and let me know CURRENT pH
=> Adding via the skimmer like this, will leave all the calcium from the cal hyp ON the filter. You will have to physically remove it from there.
=> Cal hypo reacts badly with almost everything, except water, borax and soda ash. Do not mess up -- NOTHING between the skimmer and the filter except pipes & pump!!!!
=> Following this process will actually REMOVE calcium from your pool water, at the cost of your having to clean your filter more.

BUT there's a next step, involving washing soda. I need to hear from you on this stuff first, however.

[StevenHB]

Yes, CYA was added via skimmer. There is *nothing* but pipe and pump between the skimmer and the filter. I have no chlorinator, ionizer, or other accessories. I'll check the pH tomorrow but it was 7.3 or 7.4 last night. Definitely won't be adding bleach tonight.

I see you cleaned up my sig. Thanks.

[StevenHB]

Ok pH was 7.5 this evening. I added the first five gallons of 6% bleach (I learned that there's 5.25% bleach, too).

[Watermom]

(I learned that there's 5.25% bleach, too).

Yes, and there is 3% sold as well. You have to check the labels.

[StevenHB]

Things seem to be improving more quickly than you suggested they would. This morning I had:
pH: 7.5
FC: 12
CC: 0.5
CYA: 20

Is there a reason to continue with the program you outlined above?

[PoolDoc]

No, it looks like you can do what you want.

You may wish to consider doing this:

1. Go to Sams Club and get their 24 pack of PoolBrand dichlor shock.
2. Use those packs to chlorinate for the next 2 - 3 weeks. Doing so will ALSO add about 50 ppm of stabilizer to your pool
3. Use borax to keep your pH 7.4 - 7.8 (Dichlor has no initial effect on pH, but a strong acidic effect, as it's used up)
4. Raise the pH to near 7.8, when the dichlor is gone.
5. Make sure your filter is full of sand and working properly (you can do the 'DE test' to check). Note the 'clean pressure' on your filter.
6. Begin using the cal hypo in your skimmer.
7. Backwash when the pressure is up 6 - 8 psi

Adding cal hypo this way will 'auto-balance' your pH / TA / CH. The cal hypo 'debris' will end up on your filter. If your 'balance' (Saturation Index) is low, some of the calcium carbonate will dissolve, raising pH, TA, & CH. But, if your balance is high, excess calcium in the water will deposit on the existing calcium particles in your filter.

Also, the fine calcium powder tends to adsorb oils and debris from the water, and then remove it from the pool, when you backwash. Using this method on overloaded commercial pools, I've been able to achieve some remarkable increases in clarity and water quality.

Of course, you WILL need a K-2006 kit or equivalent, so you can keep an eye on the process.

[StevenHB]

Thanks, Ben. I have your PS-232 (I think) from some years ago so I can test all of the things that you mention.

For what it's worth, I have a DE, not a sand filter.