Very Sick Fish

I don't know at this point if there is anything anyone can do to help my fish. I received about six guppies last July from one of my daughter's friends. I had them in a 5 gallon tank. They were VERY prolific breeders. In the meantime, I added another tank in order to separate the males from the females to control the population, and added few store-bought guppies. I bought my son a pair of Platys, which I put in the 10 gallon tank with the male guppies. They (Of Course) bred and had 9 babies (I have one baby left, and it doesn't look like it will be with us for very much longer). A couple of months ago, I noticed the males in particular were looking sickly, and very quickly I lost quite a few of them. Then I started losing females as well. I had been doing 25% water changes either once a week or every 5 days or so. I also had been adding a teaspoon of salt to the tanks when doing water changes. I tried raising the temperature and adding more salt. That didn't work, and I think it made them worse. At first they were lethargic, had no appetite and then lost weight and got very thin. Then they started looking bent, so I don’t know if they have TB or some other disease. Right now I have three male guppies, two platys and one cory in the 10 gallon tank. One of the guppies seems to have no control and swims sideways, upside down, etc. But he still eats. The other two guppies actually look not too bad, though maybe a little thin. The platys look fine and it’s hard to tell on the Cory. I actually found two new Platy babies in the tank last night. The guppies’ gills look red and inflamed. The female guppies look much the same. They are very thin. I just tried a week of Melafix antibacterial treatment. It seemed to improve their appetites, and they look a little better. I was going to buy some medicated food online, but not sure what to buy.

Salt is sometimes used as a medication, but not all aquarium fish can tolerate it. That could be the problem. You can gradually decrease the salinity by changing part of the water every day for a few days. Just add a good water conditioner for the replacement water. Have you checked for ammonia and nitrite? It's, of course, possible to introduce diseases and parasites, but most ofter when fish get sick it comes down to water quality. The wrong temperature, sudden changes in water parameters, and the presence of ammonia or nitrite all weaken a fish's immune system. That's what makes them sick. Medications are easy to over use and will not correct a water quality problem. Some meds can cure specific diseases when used exactly as the directions say. However, by the time a fish looks sick, it's often too late to help.

In case I haven't said it before, welcome to our forum. I hope some of the above helps. Please feel free to ask more questions and offer comments.

The salt I haven't used in a while. The medication said not to do water changes until after the treatment course (7 days), so I haven't. I will continue with water changes after today (last day of treatment). I think I just had too many fish very quickly and overloaded both tanks. I do have an empty 10 gallon that I am tempted to start fresh with and just buy new fish! I'm afriad that it too will get contaminated. I'll just keep trying, and see how many fish I end up with

If you have charcoal in any of the filtering, you need to remove it when you medicate. Since you read the directions, you probably already know that.

If you decide to start up the ten gallon tank, use some gravel from the established aquarium, and be sure you have a kit to test for ammonia and nitrite. Once its fully cycled, you should have no problems if you don't over feed or over crowd. You may want to consider making it a single species tank; that way you can make it ideal for the species you select.

I'm very wary of letting anything from the old tanks touch (i.e. contaminate) the new tank. I am thinking I should get some gravel from a friend's tank to help it to cycle! As far as keeping one species, I really like the guppies, but seem to be having better luck with the Platys! I haven't made any decisions yet though.

So i breed guppies, and TRUST me i know exactly what you are going through. Something like this happened to me not to long ago, and i ended up doing the exact same thing. I went to petsmart, bought a brand new tank with new gravel, cleaned a big rock from the other tank and stuck it in there to let it cycle. By the time it was done cycling the sickest fish died, and the rest were getting better, if not already better, so i transported them, and all but one improved 100%

So this may be the best thing for you to do, and try to get the biggest size tank that you possibly can. The bigger, the easier to maintain. If you do this though, I would not put the very sick fish in, like the guppy that can't control his swimming. Also, before you put your fish in the new tank after it is cycled, you need to make sure 110% that the ammonia level is at 0 because your fish's immune systems are very weak right now, so any ammonia could be fatal to them. I wouldn't worry about your Cory, my fish have been sick the 3 times and mine has never gotten sick yet, so i assume they are very hardy. When I had platys, i noticed that they did not get sick right away when the guppies did, but they did get sick eventually.

Just do lots of water changes, and don't do anymore salt. It never worked for me with guppies. Good luck.