And comparing the number of species that occupy either system is absurd, since both groups include many species that are not available or appropriate for keeping in an aquarium. At a guess, there are more freshwater fish species available and suitable for keeping in a tank than there are saltwater--though of course the reverse is true for invertebrates.
Kind of interesting--there are lots of SW sponges available in the trade, but few, if any, of the FW varieties.
Kind of interesting--there are lots of SW sponges available in the trade, but few, if any, of the FW varieties.