Originally Posted by M4fossil
What can anyone recommend for a sick Jack Dempsey? He's lethagaric, only getting off the bottom when he feeds. Has diffiiculty swimming, goes in spirals and is "bent" in the midsection. When first noticed months ago he had a large pooh blockage and looked to have oblong eggs near the anus. Have not seen any pooh blockage or egg like deposits since. He shares the tank with two large Oscars, one of which has habitual eye issues and a large pleco. Its a 75 gallon tank and it gets a 11 gallon partial change every week, water tests well.
My local store doesn't seem to have any recommendations left to give....
Could you possibly post exact readings for ammonia,nitrites,and nitrates? What foods are fed? What type of filtration (gallons per hour)?
In the meantime,, I would perform water changes of 20 percent once every three days for a while. I say this because it is doubtful that water tests fine with the particular fish you have in 75 gallon tank with water change schedule you posted. These are serious waste producing fish that are in crowded condition at the moment and the waste they create would make keeping water quality that these fish need quite difficult.
Poor water quality is often directly responsible for poor health of fishes and for the tank and fish you have,, water changes are critical. I would as mentioned perform water changes three times a week of 20 percent , too large of water change at once could further stress the fishes and small frequent changes in this case would be less stressful.
It is near impossible to properly diagnose what may be ailing the fish over the internet or to prescribe proper treatment but by taking steps to improve the enviornment that the fishes are in, you can improve the fishes general health. Healthy fish can fight off many of the health issues that present themselves much like humans can fight off colds and such.
I have kept, or am keeping the fishes you have, and 75 gallons is small for the number and potential adult size and waste that these fish produce. Were it me,, I would be looking to reduce the numbers of fish or,,,place them in much larger tank.
It may be too late for the Dempsey but in present tank,,, it is in my view only a matter of time before all of the fishes begin to suffer.
Do read up on the care of Oscars and the Dempsey. I believe they can be found in the fish profile here,or you may search elsewhere.