Assumption: Water quality is always degrading.
By that, we mean as far as the animals in our closed system are concerned, things are always getting worse! The good stuff like essential minerals and trace elements are being depleted, and the bad stuff, pollutants, heavy metals, are building up. If you notice a problem such as corals closing up or a sudden algal bloom, a good starting place for addressing the problem is a water change.
A number of small water changes are slightly less efficient than a few large changes. Published studies indicate for example that one 30% change is the equivalent of a 26% “continuous” change. With many small water changes, you are obviously removing a little of the new water.
The advantages of small water changes include:
- less stress on the animals
- usually easier to do, so less stress on the reef keeper
- doesn’t change the water levels in the tank
- can often be done without shutting off the return pump(s).