RD.;4979740; said:Discus breeders learned a long time ago that while they got greater hatches in softer water, the juvenile fish grew at far greater rates when raised in hard water. Freshwater fish kept in hard water (>250 mg/l alkalinity) will spend less metabolic energy on osmoregulation than fish kept in soft water (< 100 mg/l alkalinity) - thus providing more metabolic energy for growth.
The following discus were raised in moderately hard water with a pH of 8.0
What was the hardness of the water that these fish were in?