Some fish species (e.g. discus and angelfish) are adapted to very soft water and require these conditions in particular for reproducing. However, the water can provide too high carbonate hardness (KH), or the pH may have risen too strongly due to natural metabolism processes, also when keeping other fish species.
In these cases, sera pH/KH-minus provides reliable and quick support. The pH value and the KH are immediately and precisely lowered and regulated. This creates appropriate keeping conditions that considerably contribute to the vitality and the fish doing well.