puffers problems

Question
I have a 30 gallon tank with a ram chiclid, a african chiclid,a unknown chiclid and two green spootted puffers. I believe their spotted puffers, they're flouresent green/yellow with single circle black spots and a white underbelly. anyway, one of the puffers seems healthy, he eats alot and swims around just fine. the other puffer doesn't seem to eat and sits at the bottom of the tank and doesn't move much at all. and now both of the puffers bellys have turned an dark ash color, the healthy puffer still seems fine, but the other one not so much. i've been expecting him to be dead when i wake up for weeks. Do you have any clue on why he's doing this and why their bellys change colors? and also, do you know when i should remove them and put them in their own tank with brackish water? do i have to put them in brackish water? will my other(chiclids) fish do ok with a little salt? both puffers are about 2 to 2 1/2 inchs in size by the way. PLEASE help me out, i really enjoy them. thank you so much for your time and expertise....Codell

Answer
Hi Codell,
  I am surprised that the ram is still alive.  Puffers are very cute but they are really impressive little predators.  They have very sharp beaks. Sooner or later one of your puffers is going to eat the fins (and likely more) off of the ram.  I know this from personal experience.   I would separate the puffers from the other fish immediately.  

-- Ron
  rcoleman@cichlidresearch.com
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