I think I screwed up the timeframe for adding the CYA on my other post -- I actually added it the night of the 23rd, so it's been about three full days, but in any event I take your point. The CYA test is especially expensive in terms of reagents -- it uses 7 ml each time along with 7 ml of water. I've maybe tested 3 times and I'm already about halfway through my supply.

I suppose you could mix up less as long as it was 50/50 if your CYA level was high. That doesn't do me any good right now. They really need to make a more sensitive reagent :-)