new tank set-up

Question
Hello!
I'm a very new fish owner and have been learning proper ways to set up a tank through experience of all the wrong. :(  Unfortunately, I haven't yet learned the different water testing processes to complete these myself, and have been having water checked regularly by a local specialty fish store, so I don't have specific chemistry levels.

I have a ten-gallon tank that has been set up for about four weeks now.  We didn't know the time recommended for a set up, or even the process or importance of cycling, and had the tank set for only about five days before adding fish, and added them too quickly.  

Initially, we added three neon tetras and three gold fin tetras.  Sadly, we purchased ill neons and only discovered after the introduction into the tank that the store's supply was infected with ich and our neons died within a week of introduction into the tank. (ich was confirmed from pet store owner, from loss of their stock)

We had also since added three black finned tetras to the tank.  Once ich was identified, the tank was treated through every method recommended to us; we raised the temp in the tank to 82-84 degrees, added slight amounts of aquarium salt, and cycled treatments of wardley's Ick Out every three days, with water changes and vaccuuming as treatment recommended on alternating days.  Treatments were continued until the fourteenth day when ick spots were no longer visible for several days.

In the last two weeks, the tank has been undergoing ammonia and nitrate spikes, which I now understand to be the cycling process that should have been completed before adding fish :(  We'd been fighting high ammonia for approximately eight days, during which we were instructed to do 30% water changes every three days.  Four ghost shrimp were added to the tank to help with any possible waste buildup. Ammonia levels then began to steadily drop and nitrates rose.  This rise was sharp and we were encouraged to complete water changes of at least 40% every other day, which we've been doing for the last five days.

We were given a bacteria builder to encourage "good" growth to help combat waste. (Since the last of the ich breakout, we've been using stress coat, Easy Balance with nitraban, and aquasafe products proportionally with every water change.)

For the first time in weeks, the fish have been more active and colorful so we hoped we'd reached a good balance in the cycle, but there's been a lot of activity in the tank, with all the water changes and water chemistry issues.  Just this afternoon I noticed what looks like a fuzzy patch on the tail of on of the black-skirt tetras and I'm worried there might be some sort of fungal infection?

Not entirely sure what to do from here...

Answer
Hello Sheila:  There is not much advice I can give you without seeing the water chemistry results.  I need to know the ammonia, nitrite, nitrate and pH level of the tank.  I can tell you that the medication that you added to the tank to treat the fish probably killed off the bacteria colony and that you should add additional bacteria to the tank.  What do you feed the fish??? how often do you feed the fish??? dave