twitching and rubbing on rocks

Question
i have a 75 gallon tank plenty of filtration, tank has been set up with 4 beautiful dempseys for three years fine, recently i did put off maintenence due to i was working out of town for a few months, i came home changed the filter, and did a decient water change...about a third of the tank, everything seemed fine untill about two weeks ago the water became grey and cloudy. now this week i notice they are rubbing on the rocks, becoming more agressive, to where they usually get along fine, fins down, and twitching or shaking.im about to do another smaller water change now .. any other hints are appreciated thanks Jon

Answer
Hi Jon,
 It could be that they are thinking about spawning, hence the twitching, but it could also be early signs of ick.  I would watch closely.  Do more water changes, maybe 20% a day for about 3 days to really help improve water quality.  I would have some ick medicine on hand just in case.

-- Ron
  rcoleman@cichlidresearch.com
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