ive been dealing with this algae for awhile scribed my rock twice etc, My phosphate is 0 and nitrate probably the algae my fish snails are fine along with the mushroom my calcium last week was high and well same with alk I just did a 20% water change 4 gallons my tank is 20 gal my alveopora hasn’t fully extended in a long time like 2 months! I’m getting worried pls help me