Flashing and Feeding

Question
Hi Ron,
 I have 2 electric blue jack dempseys and 3 convict fry in a 60 gallon tank. Well, one of the jacks died this morning from an unkwown cause. I was trying to get them to eat something besides bloodworms and I think it may have starved because I stopped feeding bloodworms and it refused to eat anything else. I resumed feeding bloodworms to the other one and it seems to be bouncing back. So, the feeding issue is one concern. Should I just feed the remaining jack  bloodworms and hope it eventually eats something else? The convicts eat anything I put in the tank. Also, all of them are flashing periodically. Ammonia, nitrite, and nitrate are at zero. What would be causing this then?
Thanks.

Answer
Hi Kelly,
  Personally, I have found blue jack dempseys to be rather sensitive and not terribly hardy.  So, it doesn't surprise me that one of them might die without a lot of cause.  
If the remaining one will eat bloodworms, then I would feed it bloodworms.

  Flashing is often a sign that there is a low-level ick infection starting to build in the tank.  Keep a close eye on things and treat immediately for ick if you see any little white spots.  

-- Ron
  rcoleman@cichlidresearch.com
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