Treat water or drain?

Here are the numbers for my 10,000 gallon above ground vinyl pool, using Walmart/HTH 6 way test kit:

TC: 3.0
pH: 7.2
TA: 200
CYA: 100+ (could not see black dot with water level at 100)

Checked these numbers with an AquaCheck test strip, and got:

FC: 3.0
pH: 7.2
TA: 180 to 240
CYA: 100 to 150

The pool water is green.

I have read several postings, and don't think most people have this much stabilizer. I believe these numbers are real, and are caused by chemicals from local pool store.

Should I pour in gallons of bleach and try to treat this apparent algae? Or drain out most of the water, and refill with city drinking water?

Hmmm, that's sort of a tough call. A WAG on bleach costs would probably be $40-$60 and you'd still have that really high CYA as a lingering problem.

If 5000 gal of city water was reasonably priced, I'd drain 1/2 of it. A 2/3 drain would be even better. You'll still have to use quite a bit of bleach (to get rid of the algae/green water) but most likely not as much and you'll have gotten your CYA manageable.

I have to agreee with Duraleigh. If you get your CYA level down the pool will be much more managable in terms of treating the algae and also in normal chlorination. Shoot for a CYA level in the 30-50 ppm range if you can.

Another vote for draining half or more.

me too - if possible drain at least half, it will be much easier to clear up the water and keep it that way.

Thanks for your advice!

Hi All,
I have the same exact problem...
Can I ask though if it is ok to drain 1/2 the pool with a vinyl liner?
I thought I read somewhere that was bad for the liner.

Also...if you do drain 1/2 of pool is it best to shock remaining water before adding new water (to kill algae)?

Thanks.
Joe

Hi, I remember a thread before the crash that dealt with a guy that had a weekend home with a pool. Since he was only there on the weekend he was running a high cya pool and basically shocking before he went home on Sunday. The chlorine lasted all week and he was good to go when he got there on friday. I also remember there was some thought that this maybe an ok way to run pools. Add chlorine once a week and keep it high enough so it doesn't go below the minimum on the best guess chart. Just a thought.
Ken

Joe,

AS long as you only drain about half your pool, the liner will be fine. As you drain, observe for any wrinkling or movement of the liner that might not come out when the water refills. If you observe something you don't like, stop at that point just to be safe.

I would suggest you refill completely and then shock. Your pump probably won't circulate once you drain below the skimmers. Additionally, you'll only have to shock once instead of twice

Thanks Dave. Good point. I'll try that.
Thanks again.