Status report: Started SLAM last night. brought it up to 23 FC after sun went down. This morning it was down to 21, with a 2 CC. Later tests throughout the day have had a CC of .5 or 0, and the FC has generally been around 21, I keep topping it up to 23 just to keep it above 20 with the sun and all that. Also put poly-fill in last night, but the only thing we saw on it this morning was the usual skimmer basket suspects.
I brushed and vacuumed this afternoon, but the brush didn't do much to the coloration. The stuff sloughs off with my finger easier than having to scratch with the nail though. This was after about 15 hours of SLAMing. Going to continue overnight, and do the overnight loss test. If we pass that, that would be the 3 criteria. Is it worth trying to raise it to mustard levels for 24h after that or should we give up and assume its iron/metal?