Enola, yes I realize that water quality is extremely important, which is why I clean my fish tanks and ponds constantly. People do in fact keep Oscars in brackish water, they, by some accounts, do better than in freshwater. I didn't say they were community fish or that they or pipefish were for beginners. I have kept most of these fish for a long time now, in many different tanks, ponds, aquariums, etc. does anyone raise Koi?