Pinecone Fish

I kept a pair after a local shop kept one healthy for a year before deciding to sell it. The shop owner said they were hardy but, didn't do well in a "new" tank. They acted and fed well only in long established setups.
I set up a new 85 gal and loaded it with live rock and several young percula clowns. I let the system run for almost a year before ordering the M. japonica pair. By then, all the live rock was recovered and fully cultured as was the rest of the substrate and refugium of the w/d filter. When the pair arrived, the perculas went back to the shop.
My pair ate within the first hour after being dripped in. They fed on plankton/spirulina gut-loaded young guppies. They didn't touch anything that wasn't alive and moving for 8 months. Then, one would hit frozen bloodworm and mysis (although the mysis were usually chewed and spit out repeatedly). I resolved myself to having to culture several tanks of guppies, endlers, and gambusia just to have sufficient supplies of young to feed the pair.
I sold the pair when my company relocated me. I don't think I'll get them again. Mine stopped bioluminescing after 6 months (for the most part). I'd see the occassional flicker but, once they adjusted to the room's, and live rock lighting, day/night cycle, they slackened off almost entirely from lighting off as they did when I 1st received them. Or, because feeder guppies didn't react to the glow as an attractant caused the pinecones to give up on its use.
Perhaps a windowless room or basement would better suit them in retaining their normal luminescing behavior.