fish dying :( please help!!!

[karatechic007]

[shadow=midnightblue:69106b304d] my fish are dying! i have a 15 gallon tank that has been established for about 2 years and i cleaned it about 3 months ago with 1 gourami, 1 blueberry tetra, 1 black molly, 1 algea eater, 1 female guppy, 2 albino catfish, and 4 tiger barbs (about to be 3 i used to also have 1 bleeding heart tetra, 1 catfish (i dont know what kind....it swam around the bottom of the tank, was silver and black, and was about 4 inches long, plus maybe 3 inch antenas (sp?) ), one more tiger barb, and one green barb. they died, and i dont know why. the bleeding heart died first, i didnt see anything wrong with it, it was possibly age. the green barb died next, i didnt see anything wrong with it. the catfish's fins looked clamped together and before it died it started swimming slower and slower, and the tiger barb looked slightly bloated...before it died it was started swimming slower and slower and then couldnt seem to stay upright, and swam in circles....2 of my tiger barbs look bloated now and are starting to have the same problems as the one that died. i have tried putting in 3 different kinds of medicines, 2 in tablet form and one in liquid form. the liquid is "a fast, effective cure for tropical fish parasite infections like ick, etc." and was recomended by someone. one of the tablet kinds is for parasites, and i have forgotten what the other was for... i have administered them according to the dosage instructions on the package, and this morning i put in smaller than recomended doses of all of them at once can someone tell me if they know anything about why my fish are dying?!?[glow=darkorchid:69106b304d][/glow:69106b304d][/shadow:69106b304d]

[TheOldSalt]

When you cleaned the tank, you didn't use any type of soap or glass cleaner did you?
I'm sure you didn't, but I had to ask.
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Have you checked the ammonia? After cleaning the tank, it would have had to start all over again with it's ammonia cycle.
What about nitrite?
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Are there any sources of possible poisoning near the tank? Has the exterminator been by lately?
Hairspray?
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Did any new fish or plants or whatever get added to the tank after you cleaned it?
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I don't think that Ick is your problem, and I'm not really betting on poisoning, either.
By any chance, did the first dead fish(es) get eaten by the others, even partially?
I suspect that the problem is a widespread internal infection. Ick medicine won't help for that. Instead, you'll need something for internal parasites and infections. As it happens, all the stuff you are currently dumping into your tank is probably doing more harm than good. Can you tell me the names of these drugs?
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My first advice is to make a big water change of about 8 gallons with purple-cap distilled water from WalMart. 58 cents a gallon and really worth it. That will knock down any nitrite or ammonia in the tank and dilute the drugs which may not be helping, as well as give you a clean slate from which to start a new treatment regimen. After that, we'll see what we can do.
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By the way, what are the pH and temperature of the tank? Have they changed recently?

[karatechic007]

no i didnt use any soap
i havent checked either the ammonia or the nitrite yet...i dont have any cash to buy the test kits yet
i cant think of any poisons....no exterminators coming by and i dont use hair spray near the tank one of my sisters might possibly have got a very small amount of windex in the tank when they were cleaning the outside of it
i added the barbs a while after i cleaned it
i dont think that there is much chance of the fish that died having gotten eaten but it is possible
i will try to find the names of the drugs
i did a 50 % water change using water purified by reverse osmosis and some well water with some aqua safe water conditioner added (i hadnt seen your post before i did it)
i dont know the ph of the tank and the temperature is about 74...the temp. might have dropped some lately due to the fact that the weather has gotten colder and the heat in our house isnt on very high

[Fish n chips]

The old salts covered it all )