Blue Exit is the new way of getting rid of blue-green algae (cyanobacteria) without using antibiotics or compounds which contain copper. Cyanobacteria (blue-green algae, slime algae or smear algae) often arise as a result of fertilization, an imbalanced bacteria situation, seriously contaminated bottom material (rotting) or too low nitrate levels. Blue Exit effectively gets rid of cyanobacteria. Blue Exit is easy and safe to use and is harmless to fish, shrimps, molluscs and plants. If there is a serious infestation, the Blue Exit treatment can be prolonged for a few days, even with a double dose.