Ok so I'll try to be brief; I SLAMed for roughly 7 days. At the start CYA was 60 (so I think I needed to maintain 24) and then droppped to 50 by the end (evaporation, vacuuming to waste & adding new water plus rain) so I kept it at 20 after it changed.
I have maintained OCLT < .5 for several nights now even as the FC has slowly dropped (9.5 last night and 9.5 again this AM..CC at .25 or so..1 drop turned it clear)
I brushed & kept debris to a minimum (usually a handful of leaves in the pool I net out each morning before work)
Filter pressure is steady
This morning when running my FC test I *thought* I could see a film in places but told myself maybe it was debris falling apart overnight. Nope, it was algae and I had to brush the whole thing before I left for work.
So, here are the things I think I've done wrong so far (please let me know if there are others)
1. I haven't vacuumed to waste in several days. I just 'net' the large debris out of the pool and when done each morning I don't visibly see ANYTHING on the bottom.
2. I brushed out underneath my ladder (the only thing touching the water) but I have *NOT* pulled out the pool light because I don't know how. I guess I am about to learn..maybe this was the culprit?
3. I have not brushed in 2-3 days (yeah I know..shame shame) because I've been really busy and it didn't appear to need it.
4. I always test in the same place every time; on the left side 1/2 down the pool. Maybe I should find a new 'less chlorin-ey' area in the water to use as my FC location?
I assume I should probably correct all 4 of those but are there other things I've missed in this process? I am getting low on test powder so I don't want to mess up the SLAM.
I quickly brought the FC back up to 20 this morning right after noticing the problem but what else should I be doing to ensure the algae is 'really gone' next time?
I thought everything looked all clear on the testing but maybe I let the FC start to drift down too soon?