Raised fc level to mustard algae shock level as water is crystal clear and no cc, with cya @ 55 raised to 36. Little more than necessary, but emptied the carboy.
OCLT: tested 36 at 2 am, 36 at 10 am. No cc.
10 am to 3 am (long work day ): 36 fc, 0 cc dropped to 22 fc, 1 cc.
Does the sunlight consumption of chlorine produce cc? I almost never register cc when drop testing. OCLT to me shows slam complete, but daytime cc is interesting, perhaps because i gave a good brushing around 11 am, exposed more organics?