So I have a free source of water for periodic fills, that being a well next door that I can tap into if needed. Now, last year when the well became available, I topped off the pool one night and the next morning there was fine black material all over the bottom of the pool (manganese?) and the FC was down to near zero. I freaked and haven't considered using that well water since. We use it for garden watering only but I'm tempted to explore using it for pool stuff since it's so convenient (and free). For a rudimentary demand test I was thinking of just adding some bleach in a quart jar, measuring FC, and then measuring again in 10-12 hours. I guess metals would be a concern...Is there a recommended suite of tests to run to see if there is anything lurking in the water? Thanks!