Chemical Help

[mreesept]

My one set of test strips test for CYA and I am at 0-30. Should I try to stabilize first or at least get close with stabilizer before starting this process? (I expect my test kit in a few business days or a week at worst)

Thanks for your help.

[PoolDoc]

No!

Go ahead, and get going before your pool turns into a green swamp!!

[mreesept]

Ok Taylor 2006 arrived and I put one dose of .5 gal muratic acid and 3 gal 6% bleach and results as follows:
( I have a 18' by 36' in ground with about 22,000 gal.

PH 7.6
TA 240
FC 1
CC 14

CYA -???? I could not get a reading. I put it the whole way to the top and no change

[PoolDoc]

Sounds like your pool may have experienced the scourge of CYA eating bacteria -- it's fairly common. The real problem is that sometimes -- we don't know when -- the bacteria 'poop' ammonia back into the pool, as the by-product.

If you didn't make a mistake in your test results, that is almost certainly the problem (FC=1; CC=14; TC= 1+14 = 15). If this is happening your pool will likely have a strong 'chlorine' smell, from the chlor-amines that have formed.

Unfortunately, it can take an ENORMOUS amount of chlorine to get rid of the ammonia. But, there's no other solution that doesn't cost even more. So, do this:

1. Let the pH go back up; it will do so on it's own.
2. Keep the pump running 24/7
3. Adjust the eyeballs so they 'riffle' the pool surface.
4. Add 3 more gallons of bleach, wait 2 hours, and retest. If the CC has gone even higher, we've found the problem.

Once you've ID'd the problem, the only thing for it, is to keep chlorinating -- but let the pH stay high (7.8 - 8.0). Try to reach 25 ppm CC, and then hold it there. After a while (and a lot of bleach) the CC should begin dropping and the FC should begin rising.

If you have a Sams Club, it may be cheaper to buy a 50# bucket of dichlor or 40# bucket of trichlor, and use them. That will not be as hard on your liner, because those will be adding CYA. Trichlor would be best, especially if you can put it in the skimmer.

BUT, if you do this KEEP THE PH HIGH. Use borax, if you need to, to raise the pH. Borax is the ONLY chemical you can safely add on top of trichlor. Add it slowly to the skimmer.

[mreesept]

I have used stabilized 3" pucks before along with shock from SAMs club but I did not measure and put stabilizer in before.

I will put the bleach in tomorrow as I am not home tonight. I will measure Chlorine before and after adding the bleach.

==============================

OOPS!! sorry


I must have done something wrong when testing for chlorine yesterday, sorry. Re checked my chlorine this morning... FC 2 CC 4, pH 7.2, TA 210
(I did add another .5 gal of acid last night and 3 gal of bleach before checking forurm, thus the lower pH this morning)
Pool still slightly cloudy with greenish tint and silt on the bottom but looking better. I may be on the right track!!!

Thanks!!

[chem geek]

You can read about my personal experience with this effect in this thread including a summary of readings and amount of chlorine in this post. Basically, your CC will take a roughly equal amount of chlorine, or perhaps some less, to get rid of it, but you may also still have ammonia in your pool from the bacterial conversion of CYA so adding chlorine in that case might increase CC even further in the short-run. There's not much you can do except oxidize it all away and chlorine is the least expensive and effective oxidizer for that purpose.

[PoolDoc]

If you can, pick up a few boxes of 20 Mule Team borax, to go along with the bleach and tabs. You're still showing high CC's even after the correction, and they clean up more nicely at a higher pH level. (Plus the CCs that form at high pH are better at killing algae!)

[mreesept]

My FC is 2, what should CC be???

I thought I was on the right track with FC 2 CC 4 and the pH and TA coming down.
I guess I am confused. Is it because my cya is 0? Is it possible that I just didn't stabilize enough in the past?
I know that I screwed up the pH and TA last year by adding too much baking soda and ph up.