New pool owner, need some guidance please

[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.