silver shark health issue

Question
Hi, I was hoping that you would be able to help me.  I have a 4 foot tank with two smaller silver sharks, ,3 mollies and 4 rose tetras.  All the fish are doing well. However one of the silver sharks (since we got him) never seemed that interested in food.  After eating both would do the common behaviour of swmin together and play.  I have had them one and a bit weeks and the one I think is unhealthy started showing sines of wanting to hide and be near the filter. Today he didnt want the other silver shark to go near him and always swam away from the other healthy one.  Tonight the shark has started to swim around crazily, going to the bottom of the tank, swimming side ways and looking like he wasnt able to hold himself up right. But at the same time not staying like that for too long before swimming to another area and doing the same thing, always going to the bottom.  The other shark is continuely going to him and trying to get close swimming side to side with it and when it goes horizontal pushes its body back to the right position.  I have been feeding all my fish flack food as well as blood worms. But that particular fish never seems to want to eat more than two bites and later eats a little from the bottom, i have to ensure to place food near were it is at the time just so it actually has a bite to eat. Can you help? Make any suggestions? Also the fish is longer and slender compared to the other silver shark which has more of a plump belly area. The only other difference is that the unhealthy acting one also has a little bit darker colouring along the top of the body.  Sorry if I am going into too much detail but I would rather give you all the facts that i can. Hoping that you could provide some light on this matter. Sandy  

Answer
Hi Sandy,
 Sadly I have seen that behavior before and it never ends well. I don't know exactly what causes it, but it almost always ends with the fish dying after a couple of days.  I don't know that there is anything you can do for that fish.  Sorry.

-- Ron
  rcoleman@cichlidresearch.com
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