My cousin had a 70 gallon sumpless tank and for some reason any fish he put in there would die, but corals would live.
Funny you mentioned that,I had the same problem for about 2 yrs before I had a sump.Couldn't figure out what it was at the time.I was also running skimmerless on that tank,now Im thinking lack of o2 had something to do with it.
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