My fish keep dying!!

Question
So heres the thing:
I wanted to make sure my fish was properly cycled before adding new fish in, or at least on the way to establishment...so I set up my 10 gallon tank and added Stability every day along with different chemicals such as Neutral Regulator for pH and Ammo-Lock (I had ammonia problems in the past with my fish which caused their deaths! So i'm quite scared it would happen again..) But anyways, I also borrowed gravel from my boyfriend's 30 gallon tank which was already established and I put that gravel into my tank, and continued adding Stability and such. But I also had bought 3 platys and 2 mollies and placed them into the tank (not dumping the fish store water in, but netting the fish out after placing the bag into the tank to have them adjust to the water temp). I had gotten the fish two days ago and I kept adding Neutral Regulator, Stability, Water Conditioner when I added water after evaporations, and Water Clarifier, and Prime (which eliminates Ammonia and Chlorine and such). I also did a 10-15% water change today to remove uneaten food from the bottom of the tank so that it did not create a rise in ammonia. I added more water in, but did not add Neutral Regulator when I put the water in. Would this cause a problem for my fish? Would it stress them out? They were doing so well right before the water change...
..Oh and I did a test for ammonia and my results came out to .50 ppm..but i thought that was alright since my tank is still being cycled. I just thought this was the peak of the ammonia levels and then it would go back down and my fish would be fine...
This is my first time keeping fish, so if you could help me out, that would be great!

Answer
Hi Niki,
 I am sorry for the delay in responding; I was out of the country.

 The key to a fish tank is not to change too much, too quickly.  There is also not a lot of need to add all sorts of chemicals to a tank (I seldom add anything to my tanks, and I maintain 140 of them!).  When a tank starts up, it needs to cycle. This takes about 6 weeks.  You should have a few fish in there during this time.  The 3 platys and 2 mollies are okay but don't add more.  Over this 6 weeks, the fish will eat and create waste. As the waste accumulates, it feeds various bacteria which then increase in number.  This is what is supposed to happen.  After about 6 weeks, the tank will reach a sort of balance with the number of bacteria sitting at their proper level.  There are various products out there which claim to speed up this process.  While you are welcome to use them, I never do.  Just be patient.   During this time, the pH and ammonia might bounce around a bit, but don't mess with it.  You should always be changing 25% of the water in a fish tank, once a week, every week, and you should do that on a new tank as well.  

 Whenever you add water to a fish tank, it is essential that the water not contain chlorine or chloramine.  (Which your water might contain depends on your water supply, e.g., municipal or a well).  If the water contains chlorine, just let it sit in a bucket for 24 hours and the chlorine evaporates (that's what I do).  If it contains chloramine, you need to use a product like Amquel or Prime to neutralize it.  You must add these chemicals to the water BEFORE you put the water in the tank.  

 You should never let uneaten food accumulate on the bottom at all. There should never be uneaten food in a fish tank. If there is, feed the fish less.  Most people vastly overfeed their fish. Feed them only once a day.

-- Ron C.
  rcoleman@cichlidresearch.com
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