Can you reduce water hardness?
Basically, a salt based water softener works to remove high concentrations of calcium and magnesium from water through a process called “ion exchange.” This process “softens” hard water by substituting the hardness minerals (calcium and magnesium) with sodium chloride (salt).
What removes hardness from water?
The presence of magnesium and calcium carbonates in water makes it temporarily hard. In this case, the hardness in water can be removed by boiling the water. When we boil water the soluble salts of Mg(HCO3)2 is converted to Mg(OH)2 which is insoluble and hence gets precipitated and is removed.
How do I lower the hardness and alkalinity in my fish tank?
The fastest, easiest way to reduce alkalinity is to dilute the aquarium water with purified, low-mineral water. Reverse-osmosis or RO units produce water with almost no dissolved minerals. You can add this water to the aquarium to water down the overly alkaline water.