Greeting's all.
My source water's total hardness is as CaCO3 215 mg/l.(no Mg)
My 300 litre low tech, NON CO2 tank currently receives 1/2 tsp to 3/4 tsp KNO3,KH2PO4,once a week and 1/2 tsp CSM+B once or twice a week with weekly 50% water change.
Lighting is 65watt X 2 50/50 6700/10,000 k CFL...