Ok, as per instructed last time, I've brought my CYA of 0 to now what seems to be around 35 and I dropped my pH to around 7.2 (it was high as is TA, but have not rechecked TA as I haven't addressed that issue yet). I have however had to add way more chlorine than was suggested by posters (using calculator) in order to get any reading that would stick. Today, I was able to turn the water from pink to clear (using TF kit) with the addition of 6 drops, (making it 3ppm correct?). However, before I could even add the additional reagents to see if it would turn pink again, the sample turned pink again on it's own! What does this mean?? And I would also like to clarify please...when the water does turn pink, it's not a very dark pink but a pale pink, is that correct?
Also,when using the quick check vial for Cl, how long does one have to take the reading? I was having a hard time discerning the shade of yellow (very pale), so I was holding it up at various angles (with white background), when it seemed the color grew deeper. Does the reading need to take place quickly for results to be accurate? Since I couldn't get a good reading, I went to the FAS DPD test which is when I got the 3ppm. I'm confused as if there were in fact 3ppm, wouldn't that have registered as a much darker shade on the vial?
Btw, water temp is only 66 degrees, and clear, so I don't think there's an algae problem.
22, 000 gal, vinyl lined...