When to replace FAS-DPD #1

[tbatti]

I received Ben's PS234 Kit in May. The FAS-DPD #1 powder is starting to turn dark grey. It seems to work OK but, does the test remain accurate when the powder starts to turn? It there a point where it has to be thrown out? My CYA is high so I need to do the DPD testing rather than the OTO. Thanks

[Poconos]

Check this thread about an experiment I did recently. I mentioned checking again toward end of season and haven't done that part yet.
Al

http://www.poolforum.com/pf2/showthread.php?t=4659

[tbatti]

Thanks Poconos: Taking a look at the thread you attached, it looks like I am still ok with my powder. Thanks again..