New pool owner, need some guidance please

[BigDave]

Well at 10% and 20,000 gallons that only brought you 75ppm cl.
Does your kit test for Total Chlorine or Combined Chlorine? That value might be helpful to know.
Your pool consumed alot of chlorine in a sort period of time.
If the bleach burned out all the remaining goo, and the resultant Combined Chlorine, and then was baked off by the sun, great! but, you won't know your done until you're sure your CC is less the 0.5 ppm and you don't lose more than 1 ppm FC overnight at shock level and maintain shock level for one more day.
It is important to get to FC to shock level and keep it there for a while.
You can't know your shock level without a CYA test.

Sounds like it's getting alot better - you'll get there.

[SteveInFLA]

Ben, no one went into the pool until Sunday which was about 3 days after I added the 15 gallons of CL, we didn't notice any problems with what you mention but we could definitely smell CL. Janet, I didn't know Walmart had a 6 test kit, I'll take a look, thanks.

BigDave, happy to see your permit was approved ! Yes, my 4 test kit does test for FC and CC, the color is almost exactly the same from FC to CC. Yeah, I think it's getting there, I have 3 tabs in the CL200 feeder and set it to 6 and there's really no new green but what was there a couple of days ago is mostly still there now.

I just got back from the P-A-P pool store and had my water tested, I'll post the results below. Please let me know what you all think and thanks.



Store Test Results:

Total CL: (no reading, they said it is "insignificant")
FC: 1.5
CC: (no reading, they said it is "insignificant")
pH:7.6
Acid Demand: No result
Total Alk: 55
Calcium Hardness: 200
Stabilizer: 100
TDS: No Result
Salt: No Result

The "analyst" that did the tests said I needed to add 1.8 gallons of LC and 18.9 lbs. of Total Alkalinity increaser and that was all (???)

[BigDave]

Steve,
Stop using the pucks, tabs, dichlor, trichlor, powder shock. Nothing but bleach / Liquid Chlorine. Your CYA (stabilizer) is too high.

[BigDave]

Your seeing green because you don't have enough chlorine for your CYA.

It doesn't make sense that the Total Chlorine should be less than the Free Chlorine - but we've already agreed that the PS testing is suspect.

If the pool smelled like the strong, acrid, icky, chlorine smell - that indicates Combined Chlorine.

What kind of CL test are you using? OTO? Yellow? DPD? Magenta?

Have you studied the dilution method? Used it? You should figure it out if you can't get the FAS-DPD test. You need to be able to track your chlorine levels at very high levels - both Free Chlorine and Combined Chlorine. You will need to be able to measure very high chlorine levels in this pool for as long as your CYA is so high.

I suspect that after running your pool up to 75 ppm less than a week ago, you probably still have alot of something in there - maybe lots of CC that's not being read.


You need to kill the algae.

Only use bleach / Liquid Chlorine to chlorinate your pool.

If your CYA is 100 Ben's Best Guess Chart puts your shock value at 25.
That's 5 gallons of the 10% LC.
Test and adjust the Free Chlorine back to 25 ( a little overshoot is OK, don't go to 75 ) at least twice a day.
More often if you can.
Also test pH each time - high cl will skew the pH test but with alk at 55 you don't want the pH to get away from you.
This requires the ability to test cl levels of 25 or more - see above.
Keep the pool at 25 until you have less than 0.5 CC and lose no more than 1 ppm FC overnight (evening test to early morning test) and then one day more at 25.


After you've cleared the algae and Combined Chlorine

You'll use Baking Soda or Washing Soda to raise your alk ( a little at a time ) and then dial in your pH.

For maintenance:
Only use bleach / Liquid Chlorine to chlorinate your pool.
Ben's Best Guess Chart puts your normal FC between 8 and 15. If it goes below 8 the algae may come back. 8 - 15 FC for as long as your CYA is 100.

Please spend some time to figure out how to test high chlorine levels.
Test often.
Report your results.
Look at the best guess chart - you may not want to swim at 25ppm FC or you may want to wear an old suit.

Be well.

[PoolDoc]

Take a look at the "Best Guess" page, linked in my signature. You need higher chlorine than what they said. I wouldn't worry about the baking soda, unless your pH is unstable.

Given your recent algae, I'd think more in terms of 6 gallons of plain 6% household bleach (or 3 gallons of FRESH pool chlorine).

You need to test your stabilizer. I'm assuming your dealer is using strips, which aren't very accurate. But if you really have 100 ppm, you are going to either have to drain or run high levels that require a FAS-DPD kit to measure.

[Watermom]

A pool store that tells you that total chlorine and combined chlorine are insignificant? Uhh, that's a bit concerning.