I've been battling algae on my sand bed and rocks since i think my tank went through a mini-cycle about 2 months ago when I was vacuuming my sand bed during water changes. I do water changes every other week and do about 30 gallons and now, just vacuum the algae off the surface of the sandbed. My tank is 180 + 30 for sump. Looks like cyano, diatoms and everything else that could grow, is Please don't mind the dirty glass, haven't cleaned it this week. This is from about 2 weeks without a water change: I've also been chasing better water parameters as well. I want to get my Alk down under 8 to about 7.5-8 and get my calcium up to 420 and magnesium around 1350+. I've dropped my alk dosing and my alk now registers about 7.7, but I havent been able to raise my calcium or magnesium. They stay at 370 and 1200 respectively. I have been raising the drip on the calcium as well as dumping cups of calcium 2 part and magnesium 2 part in at a time. Could the algae be related to the low calcium and magnesium? I keep my phosphates under .10, closer to 0.0-0.4 and nitrates stay at 2 ppm.