Cycling With Fish Day 17 Help!?

Hi,
Just got back into the hobby after being away for about ten years. I was hoping you guys could help me out with some questions. My 36 gallon has been set up for 17 days now and I have been doing water readings every 2-3 days. I added 3 tiger barbs around day 2 (I know I wish I would have done fishless cycling, but local shop swore this was the way to go). The fish have seem to be pretty healthy and these are the water readings I keep getting, with little to no change:

Ammonia - .25ppm (sometimes veering towards .50ppm, but not quite there)
Nitrite - 0ppm
Nitrate - 0ppm
Used the API master test kit

I changed around 10-12 gallons of the water on day 7 and topped off the tank with about 1.5 gallons day 12. De chlorinated the water. When I first set up the tank I added the API quick start bacteria, but have not used it since based on what I have read. I feed the fish two small meals a day and the tank temperature is between 78-80.

Are things going as they should? Am i doing things right? I expected I would see a higher ammonia level by now and some sort of rise in the nitrites.

Any help would be awesome.

Thanks!

Ok, will do. Thanks for the help. Are the more frequent water changes for the sake of the fish, or does it help the bacteria colonize, or both?

So does the ammonia getting to high inhibit the cycle?

Thanks for the help guys. Talked to a lfs and they are going to take my tiger barbs and let my use one of their old filter medias.