i will be keeping the discus in their own tank and the new tank will be pH 7.5-8 and medium/hard as this is my tap pH. could i not add the perch with the dats if i had lots of sheltered areas for them and held back a bit on the flow rate?
Why bother? In reducing the flow for the
Ctenopoma you'll be wasting turnover and diminishing water quality so far as riverine fish are concerned. Floating plants will just get blasted around the tank, removing the cover the
Ctenopoma need. If you want a climbing perch for a riverine system, have a look for the (subtropical)
Sandelia spp. Wildwoods has had them in stock, but they are admittedly very rarely traded fish, and very much fish for expert aquarists. Otherwise, take a look at
Pristolepis, which are quite widely traded now. They are lovely fish, and not at all difficult to keep, despite being "leaf fish".
Cheers, Neale