What kind of algae

[PoolDoc]

I'm using taylor K-2006 test kit with FAS-DPD chlorine test. This morning the test results were
I have put 13 gallons of 12.5% liquid chlorine in the pool so far and still can't get to shock level. I tested the strength of the liquid using a method from another post and it tested OK. What is happening to all this chlorine?

It's very unlikely that your 12.5% bleach is 12.5%! For a 23,000 gallon pool, 13 gallons of 12.5% bleach will add about 65 ppm of chlorine.

Do this:

1. Complete the Pool Chart Entry Form
2. Add 4 gallons of your bleach, via the skimmer (remove 110% of chemicals, tabs, debris etc. from skimmer FIRST), with the pump running, in the evening, within 2 hours of sunset.
3. Wait 1 hour, then test pool FC levels
4. Test again in the AM, not more than 2 hours after sunrise.

But . . . if you don't see at least a 15 ppm FC level in the EVENING test . . . that bleach has cooked off. Try again with plain 6% Walmart bleach, but use 8 gallons, instead of 4.