The KH level, also known as Carbonate Hardness or Total Alkalinity, is incredibly important in your pond as this measure the buffering capacity. This is how well your pond water can prevent drastic changes in the pH level.
The level of KH which your pond water should read is measured in degrees of carbonate hardness, dKH, this reading should be between 5dKH and 8dKH. A pond keeper should always strive to maintain the appropriate level of KH with the reading not being below 5 dKH.
KH is how much carbonate and bicarbonate is dissolved in the water. As suggested by the alternative name of total alkalinity KH raises the pH level of your pond, the carbonate and bicarbonate are consumed by the buffering process, as KH neutralises acid the level of these two compounds can be affected greatly by the process.
In addition to this Kh is also consumed by the production of carbon dioxide, and by the nitrifying bacteria which convert ammonia into nitrates and nitrites.
The KH level decreases at a faster rate when:
The Kh level increases are largely due to the amount of natural waste within your pond:
A low kh level leads to the pH level being low, this means that the water in your pond is becoming more acidic which can lead to:
However, a high Kh level can cause your pond to become too high in alkalinity which can cause:
In addition to the factors that do affect the fish there are some changes that are not always obvious but are worth noting as these changes can indicate that the carbonate hardness may have deviated from the healthy normal levels:
Although not all these situations may occur, the total alkalinity of your pond should be regularly checked and maintained.
To help prevent a detrimental Kh level there are a few things that you can do:
