I've got lots of problems! Hopefully this forum can help.
For awhile now, I've been noticing that the water is cloudy when I turn the jets on, and it clears up immediately when I turn them back off. There were a few times I really wanted to get in, and all the levels looked fine, so I just added some MPS before getting in. Probably a stupid move. It's gotten worse. (No, the air jets aren't on! I promise, it's cloudy water, not bubbley water.)
Now after about a week of cloudy jets-on water, if the test I'm doing is correct, the demand is ~15ppm over 24 hours with a covered spa and 40ppm CYA. I'm using the TF-100 chlorine drop test. Almost every time I do the test after waiting a day, it shows .5 ppm (or 0). Every time I've opened the spa cover, though, it has smelled more and more like chlorine. I've done the test 3 times (and added back 15 ppm, shock level, each time).
I thought maybe the test is coming out wrong? So I did the daily chlorine test today. It confirmed 0 total chlorine. (Maybe the smell when I lifted the cover was residual gas from oxidized stuff? I'm very confused..)
Regarding the cloudy water -- I cleaned the filter and that didn't help. I thought maybe it was a dirty filter since circulating more water through the filter was causing the issue. But, no such luck.
Should I just do the 100ppm disinfect, drain, and refill? Seems wasteful, but shocking continuously doesn't seem to be working. The water is only a few months old, and I've been following the dichlor-then-bleach method.