freshwater and marine fishes in one tank

Bored?

Is it just me, or do those fish look like they're a little bored. Shouldn't there be some plants or rocks or something in there for them to explore?
 
Such "conversions" are fairly commonplace, but the long-term health of the fish involved usually suffers.
 
the fishstore guy showed that to me before. i would have done it the other way, koi are really tough and can take water with higher salinity. once medicated a koi in salt and i noticed he wouldn't make it so i dumped in a bunch of salt and a lot of ice and 2 days later he was still alive.
 
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