I live in an area with hard water and high nitrate but would like to keep a small tank with south american dwarf cichlids but don't like the idea of having to run an RO unit and wasting 90% of the water. I also have a 600 ltr tank that currently houses convicts, severums and BP's so if I run an RO unit to provide water for a smaller tank of dwarf cichlids can the 'waste' water from the RO be used in my main 600 ltr tank or would that be damaging to the convicts etc?
Cheers
Cheers