Intend to keep and breed discus at home. How many fish could i keep in my 120 litre tank? i know the tapwater in this area is far too hard and alkaline for these fish to thrive. However i am unsure of the different ways of treating the tapwater to suit these wonderful fish. Could you please outline a variety of methods of adjusting the water, ranging from the simple and cheap to the highly technical and expensive? Also i heard that fish produce waste - what are my options for keeping the water quality good?
thank you in advance for your valued advice