FC and CYA Problems

[Duk]

I have been a user of the BBB methods for approx. 5 years now with the occasional wandering off the trail. It seems I have made a critical mistake of having some water tests performed at my local pool store and more to the fact, I took them at face value. Bad mistake! I have a PS 233 test kit and just recently restocked it here on TFP. My problem was that I was having a lite bloom of algae which I kept treating and brushing but it kept coming back. I have put about 33 gal. of bleach in the pool over the last 2 weeks and I could not maintain any FC for more than a day. The store tests indicated I had 50 ppm CYA and 0 CC but I could not maintain the FC level. I have shocked 3 times with the FC coming back to 0-1 ppm each time. Last nite I tested my CYA level myself and showed zero on 2 separate tests. I added 2.8 gal. of bleach last nite and put 7 trichlor tablets in my dispenser , and circulated all nite. pH was 7.7 last nite and FC= 1 ppm, TA=100 ppm CH=250 ppm.
This morning, my reads are pH= 7.3, FC=5.5 ppm,CC=.5 ppm TA=70 ppm, and CH= 250 ppm, CYA still reads 0 ppm.
I am planning on adding 2 gal. liquid stabilizer, aerate, and continue to inject w/ the trichlor tablets and bleach until this evening. I may add 2 # of Borax and not aerate anymore until I see where my pH settles. I don't understand how all of my CYA disappeared, but that seems to be why I am eating so much bleach now. The pool is clear and sparkling with no signs of algae at the moment. Pool temp is 81 deg. F. Is this a good approach and what else should I do to get the pool back in balance? Thanks for your help in advance.
Larry

 

[Duk]

I thought my pool description was still up, anyways, the pool is a diamond coat plaster pool/spa , approx. 24,000 gal. w/ DE filters and water feature, (water falls), approx. 7 years old.
Thanks,
Larry

 

[PaulR]

Trichlor will take a long time to bring up your CYA. Each puck doesn't add that much, in 24k gal an 8 oz puck is worth about 1ppm; it's the cumulative use over time that becomes a problem. If you're trying to bring up your CYA within a week, you need to add the pure CYA directly.
--paulr

 

[frustratedpoolmom]

Hi there.

Can you put your pool equipment/specs in your signature? Go to User Control Panel, then Profile, then Edit Signature. (You are allowed 5 lines of text.)

Is this an inground pool, and do you close it for winterizing?

Save the expense on the liquid stabilizer and just use the granular, put some in a sock and let it dissolve in your skimmer.

I'd skip the pucks, they won't build the CYA fast enough for your needs and they are just lowering your PH/TA.

 

[Duk]

It is an in-ground pool. We do not close it up for the winter as we are in the Houston area. The pool is circulated 6-8 hours/day with 3 hours of pool sweep time. I maintain pH and minimal Cl in the winter.
Thanks,
Larry

 

[Duk]

I just now tested for ammonia by-products. The test strips (Jungle Lab Corp.) show between .25-.5 ppm NH3/NH4. I assume I have had the dreaded bacteria convert my CYA to ammonia. I have added 2 gal. of stabilizer (my wife had already gone to pick-up before I got the granular advice) and have turned down the chlorinator (pucks). I will add granular later to build up to 40 ppm CYA. Do I need to plan on shocking the pool tonite?
Thanks,
Larry

 

[frustratedpoolmom]

Yes. If you do have ammonia it takes a lot of chlorine to oxidize it. Hope you have POP onhand too...

 

[anonapersona]

Just a question for the pros who know.... I read pretty often here about a pool closed for the winter getting ammonia with loss of CYA. But, for a Texas pool where it runs all winter and is not covered (assuming no cover), how do you get that ammonia started? Are we looking at a lot of debris left in the pool, something died, or is this someone peeing in the pool?

 

[frustratedpoolmom]

It doesn't have to be closed for the winter...the FC just has to drop to 0 for an unspecified amount of time and bacteria is introduced in some way.

 

[chem geek]

It doesn't have to be closed for the winter...the FC just has to drop to 0 for an unspecified amount of time and bacteria is introduced in some way.

The time with zero FC can be very short -- just 3-4 days -- as was my case described in this thread. I have 2000-3000 ppb phosphates in my pool and probably lots of nitrates as well -- it's a lovely soup for bacteria and algae so is rather unforgiving if the chlorine gets too low. For 6 years I managed it great with chlorine alone and then slipped up once. Now I've got 50 ppm Borates in the pool and I'll do an experiment at the end of this season to see if that helps prevent such a rapid event (or even algae, since the water became cloudy when this happened to my pool).

Richard