Where to start now?

[bonze82]

I got lucky and some tropical weather dropped my cya way down to around 10 and ch of 210. I had mustard/black/green algea and I think I managed to nick the mustard and green algae out of the pool Finally. I'm still fussing with the black algae shocking nightly with a mustard dose and a brushing daily. Last pool test results:

cl: 1 - yes I know it is way too low I think it is due to an algae bloom trying to take off still
ph: 8.1 - Issues keeping between 7.4-7.8
ta: 80
ch: 280
cya: 20
salt: 1000 - fresh water pool
The issue: I've run into what looks like mustard yet it can't be brushed off the bottom of the pool so I'm thinking it might be iron or other metal/mineral from the exposed gunite from the severely damaged plaster. (Thanks other pool guy for keeping the ph below 6.8 for 3 weeks and cya over 160 with zero success on removing black or mustard algae 10 pounds of trichlor a week!) So whats next?

 

[Sharelick]

Can you post a picture? It seems black algae is rare so you likely need to SLAM your pool. At least run the OCLT.

 

[bonze82]

The overnight chlorine loss test is 7ppm loss no combined chlorine. I just checked my city water as it was smelling bad again:
fc: .5
cc: 3
ph: 8.2 - was 7.4
ta: 190 - used to be 80ppm
ch: 0 - used to be 300ppm
Previous city water test results are from 3 years ago when I couldn't get the ch to come down I tested them. Is their a chance the water balance issues are from me adding water daily due to the pump leak 3 seals in 3 years and it still leaks. I also suspect a plumbing leak. I'll post a picture tomorrow.

 

[Msch99]

How did the tropical weather drop your cya? How long ago was the 160 cya test?

Adding chlorine once a day makes for a long drawn out slam, but those of us who work don't have much choice. I would at least add in morning before work, just after work and before bed. Try to maintain at least the target for your cya when you retest.

7ppm overnight loss calls for a slam, regardless of CC.

CH= 0? Not sure that is possible?

How much water are you adding daily?

 

[Sharelick]

7ppm overnight loss calls for a slam, regardless of CC.

i agree with Msch, also what are you using to as a test kit?

 

[bonze82]

I'm using a hth 6 way test kit for ch and ta just used the remaining cya as thats the only reagents I have left using a cheap chlorox test kit for the ph and chlorine I know they suck I know they aren't approved better than flying blind. Shocking at night seems to have a better effect than during the day. In the pics I circled the damaged gunite in black what apears to be black algae in red and the suspected mustard in yellow. I listed the city water to give you guy's an indication of the fill water used yes the water does have a ch of near 0 an alkalinity of 180 and a ph of 8.2 with salt of 0. We had 24 inches of rain in 2 days about 3-4 weeks ago drastically changing my chemistry.