Swordtail

Question
I've had 2 female swordtails for several years--both more than 3 inches long. The male carcass disappeared--and I found him under the credenza when I moved the whole tank about 2 months ago. I replaced the male, and a month later, his carcass was found under a piece of bogwood.

Last week, I could see the larger female (all orange) had a definite color differentiation to the end of her underside...translucence. One morning she was "resting" head down against a bogwood with a swelling that made me think she was about to give birth. The next morning, she was dead with many small globules that looked like germinating quinoa coming out of her vent area: I thought they were maybe babies coming out and she died in childbirth?

Today, it looks like the other female, who is orange head with black tail is loose skin and scales on one side of her peduncle. Like 5 to 7 of them. So now I wonder if this is some sort of a wart disease? I clean the 90 gallon community tank gravel with approx 20 gallon water changes weekly (just did this yesterday).

Answer
Hi Jenelle,
I believe some investigative work is definitely vital in this situation. There will have to be a process of elimination to find cause of the swordtail deaths... the first thing would be to test the water for ammonia,nitrite and nitrate. The levels should be as follows- ammonia-0 nitrite-0 nitrate-20 or less. Once we have the possibility of water quality problems out of the way, we can move on down to other things.

The symptoms you described are unusual. My first thoughts are some of the swordtails are dying of old age, or old age-related problems. Since you said you had them for several years, they may be at the end, or nearing the end of their life. It can happen very suddenly that a old fish will show symptoms of old age and not long after they can be gone. Organ failure can be possible which may have caused the swelling. Its possible the female may have been too stressed while having fry or may have had an internal problem which caused her death.

Another thing, besides the female missing scales, do you notice any beginning symptoms that are warning signs like gasping, listless behavior, not eating. These can all be symptoms of old age as well as beginnings of an illness. But i dont feel i can diagnose this definitely and recommend a medication. Medicating blindly can do more harm than good.

And are there any fish that might be  picking at the swordtail? How are the other fish behaving? I believe if this was a true disease it would start infecting all the fish. If you are worried, try separating the sword tail into a separate tank and monitor her closely. I feel this swordtail problem has been more an individualized situation rather than a real dangerous illness problem.

With a little investigative work, i think you will be able to get a better idea of what might be going on.

I really hope this helps you and happy holidays!!
Susan~