cichlids suddenly died

Question
Hi, had 4 cichlids (Lk Malawai type?) Father is the big blue with vertical stripe, Mom is spotted light & drk. brown. I was raising 4 offspring, 2 blue males, 2 brown females, approx. 5 months old. All was well. Did water changes, checked levels with 6 test dip sticks, all well. All of a sudden they were at the top of the tank, nose to the edge of water. Levels still good. Did 1/3 water change, new filter, BUT did see three pieces of food at bottom of tank that were fuzzy. They normally ate everything in sight! Removed the nasty gravel, siphoned remaining, water very clear, still good test results. Next day, the two girls were both dead. One brother was doing not very well, did another small water change, used some Quick Cure, and they seem to be on the mend. How could this have happened when I was getting good water test results, and these fish were always healthy since birth. I also added an extra air stone. They are in an Eclipse tank with the filter and Bio-wheel in the hood. I am saddened by the loss of the sisters and want to do what I can to prevent losing the brothers. Thank you. Terri in IL

Answer
Hi Terri,
  How large a tank is it?  Is it possible that the one "healthy" fish was attacking the others?  The number one cause of cichlid deaths is another cichlid.  

-- Ron
  rcoleman@cichlidresearch.com
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