CYA at 450 ppm? Or did you mean Calcium Hardness?
I don't know of any CYA test kits that allow you to test higher than 100 ppm, unless you're diluting your water sample.
How about getting your friend to log on to this site, or the other active site, www.troublefreepools.com.
They are so much better knowing how to maintain their own pool and will owe you MORE for helping them learn how to take care of their own pool.
I can check with my local reps to see who they would recommend.
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