Originally Posted by greentab
i have a red tail catfish that has a round white spot on the back of his tail and i have no idea what it is i think maybe an Ulcer. just wondering if any one knows?
It is very difficult to properly diagnose over the internet without photo and all information you can provide about the tank the fish is in.
Were it me, I would see that test results on my tank = zero for ammonia,zero for nitrites,and no more than 20ppm for NitrAtes. Could be any number of things causing the white bump or spot you describe but maintaining the water parameters will offer the fish the best chance of recovery with or without medications which in my view,should be considered as last resort. If water conditions are not of good quality, then medications will have no effect.
How long have you had the fish? what size tank? what foods are offered?(hopefully no feeder fish) what is your water change scedule? how much water do you change and how often? can you test water or have it tested at fish store and then post results for ammona,nitrites,and nitrAtes? Need numbers for these results not words like,OK,normal,good,etc.
What type of filtration is being used? what size filter and what specific filter? The fish you speak of as I mentioned in another thread, grows quite large,requires heavy filtration,frequent water changes,and vaccuming the substrate is a must. If you can provide some more info, then perhaps those who can help will have a better idea as to possible causes for your concern.
At this point,given NO information, all one can do is guess.