How to test High Chlorine

[fcfrey]

I just read the entire thread started by DonnaElvira on this page and I have to ask ----- How are we testing for a high Cl level? I use a Taylor DPD test kit which, as I have read many times on this site, is not capable of reading above 5 PPM. Other than the "shotglass" method, is there a test kit out there that I should get. Again, with the bleaching action of high CL levels and the comparator only going to 5. I'm stumped!!!!

When I do shock how can I tell if I've reached breakpoint chlorination if I can't test that high of a level accurately? It takes about 24 hours to turn the pool over with the 29000 gallons at 70 GPM through a DE Perflex filter. At the end of the first day the Cl is off the chart but where???? Do I really need to know? Ben's Best Guess Cl for CYA dictates a given level. So, again, How do I know where I am?

Latest test results are:

FC 1.5
TC 1.5
CC 0
TA 90
CYA 50
pH 7.7
CH 230
Temp 82
Phosphates < 100
29000 Vinyl IG
Crystal Clear ---- No Problems and don't want any!!!!!!!!!!

I am making the transition to BBB so I am keeping close track of things.