How often do you need to do a water change?
How often do you need to do a water change?
How often you have to do a water change can vary greatly. Influencing factors are, for example, the aquarium size, the stocking density and the amount of planting. In a nano tank (especially those without a filter), an aquarium with many animals or little planting, it is recommended to change the water once a week to regularly mix the old water with new. For larger aquariums with little stocking and a large amount of plants, a water change every 3-4 weeks is sufficient.
For an average tank, a change every 2 weeks is usually sufficient.
How much water needs to be changed?
As a rule, it is enough to change about 30% of the aquarium volume at once. For nano tanks or aquariums without filters it is recommended to change about 50-80% to replace enough water with new. In case of emergency (for example, too much nitrite) you must change at least 80% of water.
Why do you need water changes?
On the one hand, changing the water helps the aquarium look better, as the aquarium water will discolor over time. Secondly, changing the water helps to reduce toxic substances and reduce the general bacteria load. If changed too infrequently, this can cause fish to develop diseases such as fin rot.