sera O2 plus - simply sprinkled into the aquarium water - immediately adds oxygen and thus improves the living conditions for all aquarium inhabitants. The breath of the aquarium inhabitants as well as other natural breakdown processes constantly consume oxygen. Certain circumstances may lead to acute deficiencies. This includes high water temperatures, strong organic pollution and oxygen consuming disease treatments. While even little undersupply already causes stress, extreme lack of oxygen often leads to the death of fish. Additionally, the breakdown processes run faster in case of good oxygen supply, thus the aquarium will remain crystal clear and without unpleasant odors.sera O2 plus+ breathe freely with purifying+ emergency support in case of acute oxygen deficiency+ stress reduction by optimized oxygen supply+ easy and safe application+ supports the breakdown of sludge