My numbers were as follows before I shocked:

FC - 4
CC - 0
Ph - 7.5
CYA - 40
TA - 90
CH - 190 (not sure about this one, but I vinyl so I don't test it often)

I went ahead and shock to 23 ppm just in case I was battling the Yellow/Mustard algae that Matt4x4 refers to.

My Ph did go up quite a bit with the shock is that normal? It reads about 7.8-7.9 right now.

I brushed and added some DE to my sand filter. I already seems to have helped. Although I won't really know whether it was shocking or the DE that solved my problem. I guess I don't really care at that point.

What is a safe chlorine level to swim at?

Thanks,

Riles