May 3, 2025 #1 T tilly New Member View Badges Joined May 2, 2025 Messages 1 Reaction score 0 Location Dixon, Ca What state or country do you live in California Rating - 0% 0 0 0 Just discovered this grey/black slime on the sand in my aquarium. Can anyone tell me what this is?
May 3, 2025 #2 Tahoe61 10K Club member View Badges Ultimate Member Reef Squad Excellence Award R2R App User Moderator Emeritus My Aquarium Showcase Joined Mar 2, 2012 Messages 18,157 Reaction score 21,873 Location AZ Rating - 0% 0 0 0 Cyanobacteria, cyano can appear in different colors.