Dianna wrote:
About the CYA test, the more water you pour into the comparison vial, the lower your CYA is. So, at 40 I saw no dot - at 50 I could make it out if my life depended on it.


Yes, of course! You're right. I screwed up. Can I please use the excuse of a pulled wisdom tooth and Darvocet to explain my confusion and error?


I did the test anyway - and now CYA reads 30. Think that's reliable after 13 mins?


IMO, yes. If I understand the chemistry of the CYA test correctly the suspension is not going to go clear in time. Just make sure you shake it before pouring it into the test tube.


With TA - I added 3 more drops - no change. I'll add more next time (too dark outside now).


Once there is no change, you're done. Adding more drops won't produce a change. Polyvue's reference to magenta is good. I see the endpoint as red but in practical terms it doesn't matter. The endpoint is when you cannot produce any further color changes with the addition of more reagent.

Keep testing and keep adding enough chlorine to maintain the shock level; eventually your CCs will disappear.

That batting filter is very creative!