I'm pretty new to the refugium world. This morning, I woke up to this on some of my macro algae.
Lights on for 12 / off for 12
Salt: 1.025
Temp: 76.9
PH: 8.2
Alk: 8.0
Calcium: 395
Magnesium: 1180 (this is a bit low)
Phosphate, Amm, Trite, Trate: 0
Anyone know what this is caused by?