All values are good, yet the water is not really clear.
It can happen that the water has the correct pH and sufficient chlorine, yet is not completely clear. This is often because there are small impurities in the spa that are too small to be captured by the filter. By binding these small particles with a flocculant, they become larger and can be trapped by the filter.
When using a flocculant, it may happen that the water starts to foam; to break down this foam, you can use ananti-foam agent.
