Clear, but no chlorine???

[BigDave]

How does the water look? Still clear? No stains?

Did you happen to test pH when the FC was below 10 yesterday?

Sounds like you are on the right track. The only chlorine demand I recall like this was caused by ammonia that was the result of bacterial conversion of CYA over winter. Maybe your pool got into this situation, the bacteria could grow unseen turning CYA into ammonia if the active chlorine was low enough. I would, however, expect to see visible algae if the chlorine / CYA ratio was so low. Maybe it was the fertilizer.

Does the pool water stink of chlorine like a heavily used indoor pool (after the cover's been open a while) or does it have little smell?

[mary jo]

The water is still very clear. No slimy feel on the walls or floor. There is no heavy smell of chlorine at all. No staining at all. (The bucket test w/ 1/2 cup bleach had no stains either).
I did test the ph on Sunday morning after I added about 2 lbs pH up to the pool sat night ( several hours before adding the jugs of chlorine). It was 7.8. The water clouded when adding the pH up but dissipates in about 2 minutes.
I did test the cya to day and it's at about 140. Is that possible considering it was so high a few days ago?

[CarlD]

I don't know how this thread got closed, but I have reopened it.

[CarlD]

Mary Jo, I haven't been following this thread but I noticed you are using pH Up! You should know three things about it:
1) It will raise you t/a as well as your pH
2) Because of that we generally recommend using Borax instead ( yes 20 Mule Team Borax!)
3) pH Up! is EXACTLY the same as Arm&Hammer Washing Soda (next to the Borax in the laundry aisle), being Sodium Carbonate or Soda Ash, only it costs 3x to 4x as much as Washing Soda.

FYI

[mary jo]

Yes, I read about that too late….! I bought a bunch of "stuff" from my (former) pool store guy before I found The Forum... 25 lbs of pH up is what they recommended. My pool's pH has been low all season, however TA has been about 80-100 level (until just recently it went up to 120). I still have 10 lbs left so I thought I'd use it up. Didn't realize it had extra stuff in it. I'll get Borax for next time.
thanks for the info.

[BigDave]

Let's not add anything to raise pH or TA for a while. I'd like to see it come down. Half a box of Borax would have had about half the effect on pH and little effect on TA. Right now (your cloud proved it) your pool is dangerously close to precipitating calcium either as a cloud in the pool or onto your heater or as scale at the waterline.

The CYA test is hard to read, I'd call 140ppm the same as 150ppm.

Keep the FC at 15ppm with bleach, if it drops below 10, check pH. Enjoy the party if you can - pool parties at my house are pretty stressful for me - I count heads alot. I really only relax when the pool gate is locked.

[mary jo]

Yes I am a giant stress ball during pool parties- and I haven't had that many yet! I wanted to ask about safe chlorine levels for swimmers in my pool. I read ( and re-read) the info about CYA /free chlorine levels , but wanted to double check with you. What is a safe FC level for swimmers given my high cya? Oh- pH is currently 7.6

[BigDave]

At 150ppm CYA, the pool is safe between 8 and 15. I don't recall if I've asked you to look at the Best Guess Chart. It explains the relationship between CYA and chlorine.

How does the pool look? Did you measure FC / CC this morning?

[mary jo]

Good Morning! At 10:00 last night I put 2 jugs into the pool to bring the FC high enough so that I would be OK until this morning. At 8 the FC=9, CC=.5 The pH=7.6 (so I'm losing much less FC per hour today!)

I found the Best Guess Chart and it makes perfect sense to me, but I guess being told for years that you "never, never, EVER want to swim in anything higher than a 4 or 5..." takes some getting used to.
I know you guys must get this all the time, but it's really like we're Neo (from the Matrix movie) and you're Morpheus and we've just taken the red pill….strange indeed.
But I get it now.
Fingers crossed for good weather- it's cool and 40% chance of rain. Can't control the weather…….
Thanks for all your help!

[BigDave]

You may want to push the FC a bit higher before the guests arrive. You're still losing chlorine at a pretty good rate and a bunch of swimmers will only increase the demand.
Pool Party Hint: If you make all the kids get out every 45 minutes for "adult swim", you'll get less pee in the pool and less chlorine demand.