Been overbusy and just getting at my pool - had to add water to fill about 4 days ago. Treated with pool magnet and algaecide and let filter do it's job before adding any bleach (well water with iron). Started getting a touch cloudy- so tested and added muratic acid to bring my ph down a tad, stabilizer was at 20 so added enough to get it up to 40, and shocked the pool yesterday.

This morning it was perfectly crystal clear, and after church it literally looks like somebody pee'd in my pool. Mainly yellowish/green color. Tested again - here's results:

FC - 5.9 (coming down off shock)
CC - .4
TC - 5+
ph - 7.2-7.3
alk - 137
cya - 40
temp - 72

I have a few leaves and some dirt in the bottom - not too bad. Started my Pool Rover Plus. For now- just gonna let my DE filter do it's job - any suggestions as to what caused it to turn yellowish?? 17,000 gal 18x34 AG vinyl liner. Thanks.