Crushed limestone (Calcium Carbonate) 1kg
Crushed limestone (Calcium Carbonate) is recommended for aquaponics systems with Silver Perch, especially when using rain or boar water. It acts as a buffer to water Hardness, which in turn helps to stabilise PH. You will have much more success growing and keeping Silver Perch alive if you add crushed limestone to your pond. Dosage varies according to the water hardness, though we would recommend approximately 1kg per 1000 Litres, or until most has dissolved with a small amount left over (un-dissolved) in the bottom of the pond. It will cloud the water but don't stress, it's only temporary and it doesn't affect the fish.