What, and that’s not the case with freshwater aquarium fish?
I would presume that for both branches of the hobby, the brightest colored (as well as smaller members) of the piscine families are selected due to their visual appeal. Of course, there are brightly colored FW fish–Bettas, goldfish, discus, African cichlids, pumpkinseeds (I used to breed them), neons/cardinals–but for the most part, they are a plainer lot, color-scheme wise. Even those which are colorful, such as neons, trout, and various sunfish types, are still dominantly silver. Regardless, these colorful FW fish cannot compare in intensity and sheer proportion of body coloring (the entire body being involved, rather than a stripe or pattern) to tangs, damsels, wrasse, parrotfish, saltwater angels, butterfly fish, triggerfish, etc.
Even comparing two solid-yellow breeds reveals a difference: the freshwater lemon labidochromis is about as yellow as they get, and it is lovely. But it is not as smooth, bright, or screamingly eye-catching as a yellow tang.
Sure, there are plainer colored SW fish. But my point and original question centers on the difference of intensity in the colors as much as the varying number of colorful breeds.
I’m beginning to agree that camoflage has to be part of it; my african butterfly (fw) is brown and mottled, to match fallen leaves that rest at the surface where he spends most of his life. There are no fallen brown, decomposing leaves at the surface in ocean life.
I used to think the world was against me. Now I know better: Some of the smaller countries are neutral.
Laura’s Stuff and Things