^^^^^^^^. Might be a minor FW phyto bloom. Make sure that you use high quality carbon, some kind of carbon that isn't rinsed with phosphoric acid, or you might be adding to the problem.
hope that helps.
Cheers,
Kurt
75gal 6x54w t5's on icecap slr's 3 blue +, 1 pro color, 1 ge 65k, 1 uvl spuer atintic, iwaki 40rlt return, mak 4 on closed loop to om super squirt, mak 3 on etss reef devil, jbj artica chiller, aquamedic calcium reactor, DIY Kalk reactor, DIY media reactor, currently running half phospahte/half carbon.
Live in Uvalde, Texas. On the fish hatchery!