Sick Jack Dempsey

Question
Hi Chris,

I need some help with my 6-7 year old Jack Dempsey fish.  His name is Clyde,
and I'm desperate to get some help.  I would say he's 6-7 inches long, living
alone in a 40 gallon tank.  We've had the most recent water in the tank tested
at our local fish store, they say it's perfectly fine.  I don't have the stats on the
water, my husband took the sample to the store.

Quick background:  Up to about 3 years old, my husband fed him fish food
and the fish seemed pretty satisfied.  Then, on a lark, we gave Clyde a camel
cricket that we found in the house.  He WOULD NOT eat any fish food after
that, so for about 2 years, we fed him crickets from the fish store exclusively.  
Then, a store clerk told us that wasn't ideal and we really needed to get the
fish to eat fish food because it was healthier for him.  So, with reluctance by
the fish, and persistance by us, we got him to eat fish food for about 6 mos.  

The back drop to the story is that the water in this tank stays really green
with algae, I mean really green.  Sometimes, so opaque that you can't even
see Clyde, which the fish probably likes, but we've been told is not ideal, so
we try to keep it as clean and clear as possible.  

At one point about 5 weeks ago, the water was SO mirky, we have to a 50%
-75% water change out.  We stress coated it, etc.  The water cleared up. (this
is a chronic problem, I think, b/c of where we have to keep the tank in our
house, it gets lots of sunlight, especially in the winter, and that encourages
algae to grow.)

So, it's been about...3-4 weeks and Clyde hasn't eaten ANYTHING.  We tried
crickets from the store, then a fish food that is supposed to treat fish who
have internal/external bacteria infections, but b/c he won't eat, that's not an
option.  We then bought some feeder fish and 4 "tuffie" shrimp, and he won't
eat those either.  This is very unusual for him.  This has been coupled with
some very strange behavior by the fish:  he's been swimming sideways every
so often, he'll turn stark white for a few seconds, then get all his color back,
and he's actually letting my husband PET him...totally weird.  Also,  he's been
sort of an active fish in the past, swimming around fast, etc., getting energy
bursts, but lately he'll go through these really erratic spells, thrashing around
violently, swimming into the glass at alarming rates.

Something's wrong, no?  He had quite a bit of extra meat on his bones, but
he's getting skinnier and skinnier.  

Any advice?  

Thanks so much,

Jenny Maness  

Answer
hey.
Im REALLY sorry to say, but i think clydes on his last fin. Most fish who get old tend to not eat, get lots of diseases for no apparent reason, and get lethargic. Clyde isnt really that old for a jack dempsey, since its about 10-18 year lifespan for them. Try feeding boiled peas for a week, and try other different foods. Try pellets, bloodworm, and anything else fish like. You can try feeder white cloud fish, ghost shrimp, and a variety. The thrashing may mean parasites as he may be trying to whip them off.

Try melafix and pimafix combined, a variety of food, boiled peas, and less tank light to make him less stressed. It is VERY frustrating when i fish wont eat. I know how you feel. My bettas and other cichlids used to not sometimes want to eat. Eventually, they got hungry and ate. Fish can last a month without food, so maybe clyde will eat once he gets hungry enough. My african butterfly was like that too. Some days, he would eat 5 crickets a day, and sometimes he wouldnt eat for two weeks.
Well, enough of my live story. Hope Clyde gets better!

And for information on fish life span, try http://freshaquarium.about.com/cs/beginnerinfo/a/lifespan.htm