derbasia

Green Hair Algae (abbreviated as GHA for this article) - Derbesia - is a form of algae that looks like its name. It is usually dark green, grows quite long if left unattended and spreads across your tank rapidly. Once this problem has begun, it can get out of hand in a matter of weeks. And soon you start to look at your tank in disgust, thinking “Why me? What did I do to deserve this plague?”