Yellow/Mustard Algae SLAM Problems CYA, PH, FC, Dichlor HELP

[cfherrman]

10 mil is x25
25 mil is x10

The no drain acid was or the zero ta treatment is to remove scale on your pool surface, not remove ch in your water

 

[mknauss]

OK -- I never bother with the 25 ml sample as my CH starts at 300 with a fresh fill.

You must be exchanging alot of water for fresh on a regular basis. Or you are in that area of Las Vegas that gets low CH water.

Test your fill water for CH, TA, and pH. Good information to have.

From your picture it looks like algae. But, you cannot brush it off or even scrape it off. So it is trapped in calcium or there is something other than algae going on.

- - - Updated - - -

You do show you have a heater. And you have also said you did not monitor pH much.

If you have had pH lower than 7.0 in the past for a long period, there is a chance the copper heat exchanger in the heater has dissolved and this is copper.

Get some Vitamin C tablets. Put a bunch in a sock and crush them up. Put the sock up against the stain. Let us know what color it changes to.

Take care.

 

[Fadderall]

Searched everywhere and cant find C tabs so I guess I will go pick some up. I have NEVER seen my PH go down to 7.0 even when trying to drop it to lower TA. PH is always sky high in this pool (out of range over 8.0 if left unattended). But, I will try the C Tab test.

UPDATE
Pool water is crystal clear. See through not even there clear, but the stains/algae persist.

Still cannot get a handle on CYA. I have now added 96oz of Dichlor which should have raised to 40 but I still can see dot at 30. I do notice a difference though now when vial is filled to top (20 CYA?) as the dot is totally gone at that point. Seems like it is still 20-30 CYA. Does this sound right? Does the Dichlor need to be added all at once or is it cumulative?

Yesterday Afternoon
FC 9
CC 0
PH 7.8
CYA 20-30
Added 1 gallon of 10% chlorine liquid

Today 12pm
FC 4.5
CC 0
PH 8 (6 drops to 7.2)
TA 200

I assume the high TA is causing my PH to always drift up fast, is that correct?
Is the high PH maybe interfering with the chlorine killing the algae/stain?

Should I do the procedure for lowering TA at this point, then stabilize PH and try to SLAM again?