I've posted my problem on a different aquarium forum and two people responded and were not helpful!
This is what I posted there:
I've had my 15 gallon tank for a few years. If I had known as much as I know now when I started out, I would've gotten a far bigger tank. Up until recently, I was only changing a couple gallons a week (but it was sometimes more like every two weeks) and vacuumed the gravel. That's only a little more than a ten percent water change. It's no wonder my poor fish are sick.
I originally had four gold barbs and two platies in there. And yes, I know now that that is overstocked, which is probably why my fish started dying. I think the problem started because I didn't know anything about water quality and gave my fish bare Ro water, which apparently has no minerals or whatever fish need to thrive. So the fish never grew from the juvenile state. And that was ok, I thought. They were still well rounded and acted normal besides being small. But, in recent months, I started mixing ro water with our well water.
But then a few months ago, one by one, the fish would start to get emaciated, the body lines became bent and they took to hiding. They had normal appetites, but no amount of feeding did anything.
And the other day I bought a tropical fish book by David B. and he said 50% water changes! I can't imagine how horrible their water must be! So yesterday I changed about 50%. And no, I don't have a ammonia, nitrate, nitrite test kit. I really feel very stupid about all this. I put off getting a test kit because it was "too expensive", but all these problems are going to cost way more, if only in stress!
Right now I'm down to two gold barbs and one platy. One gold barb looks really bad: emaciated, shredded fins, bent, and sitting on the bottom. I would be surprised if he lasts the day.
But now I'm really worried, because if they do have TB, I could have it, right? I garden a lot, so my hands often have little cuts and scratches, and I've never used gloves when I do stuff with the tank.
For some reason, I can't get my computer to upload my photos. But my last gold barb looks like this.
I just read something interesting on another fish forum: something called "Skinny disease"? not actually a disease, just something to call it when the fish has parasites and other factors leading to anorexia and death. Can someone please help?
Do you have recommendations for worming treatment? I bought some aquarium salt yesterday and put the recommended amount in the tank.
I went on vacation and just got back a couple days ago and now I'm down to just the platy. He still looks ok, except his dorsal fin edge is a little ragged and he's hiding. I made a big water change today and plan on doing another one in a couple days. I went to walmart and looked at the fish tests but all they had were the dinky test strips which I heard are notorious for not being accurate. As soon as I have the funds I'm going to petco or petsmart and getting a real kit.
Everything I've read on TB matches with what my fish had/have. I bought a pair or gloves for myself to use when I do maintenance, but if it is tb, I'm really discouraged about fish keeping. It seems so sad that I would have to start all over, back to square one.
Really all the two members said was "don't worry, Tb is really rare". . . NOT HELPFUL