Trust the cheapo OTO/phenol red drops kit. Ditch the AquaCheck strips.

=> *ORDER* the K2006; we've still never heard of a pool store carrying these. (Why would they stock a kit that will tend to put them out of business.)

=> Any pool store that tells you to add calcium to a vinyl pool is not to be trusted: they are selling you chemicals that are worse than useless in your pool, since they have NO benefit, but can cause problems.

=> If your pH is between 7 and 8 --AND-- your chlorine is greater than 1.0 OR 10% of the CYA level, whichever is higher --AND-- you haven't added any funky chemicals like foamy algaecides, mustard algae treatments or non-chlorine shock . . . it should be fine.

=> Wait time after adding chemicals is often 5 minutes, but it depends on your pool, where you added them, what you added, and how the pool circulates. If you want a safe number that's pretty much arbitrary, but almost certain to be safe, then go with "1 hour after chemical additions WITH THE PUMP ON and CIRCULATING".