Took my 234 test kit over to my brother's 16 x 32 inground (18,000gls) vinyl pool and here's what I got......

Water is crystal clear, traces of algae visible.

FC 0.......(out of town for week nobody added chlorine):ma
CC 0
TC 0
pH 6.6
Alk .....Turned red immediately?
CYA...110

He has been using sodium dichloro-s triazinetrione dihydrate from Sam's Club I think. Available chlorine 55%

I added 2 cups of this to bring up cl level.

What else do I need to tell him to do?

Sand filter running 24/7.


Thanks!

PS I'm in the process of converting him to the 3 B's!