I also saw a bigger dent in algae where they got more light vs shaded if that helps any.Alright, you inspired me! I doubled the dose to 50 mg/gal (13 mg/L). Also dropped the photoperiod to 8 hrs from 11 during the week. Tank gets some daylight this time of year.
Params:
1.025, 79F, ph 8.3, Alk 8.5, Ca 500 (probably not true), NO3 and PO4 not detected, with the caveat that all my tests are expired so who knows. Probably should get new kits or make up some standards to calibrate against.