Betta Fish and a 5 Gallon Fish tank..

Question
Hi there..
I just recently purchased 1 betta fish and a 5 gallon fish tank. When I say recently, I mean, 2 days ago. The store I purchased all of this from told me to do the following.

Clean and rinse all accessories and tank including filter with tap water. And then I put the Betta in the bag to sit in the water so it would climitize.  

Everything went well, until yesterday evening. I noticed the tank was beginning to get cloudy. Then today, it was very noticeable.
I went back to the store tonight and purchased (on advice) Betta Water Conditioner (and I also purchased Betta food) I was told to empty the tank, rinse everything again, and put the Betta in another bowl of Bottled water till morning, and then introduce him to the tank again.

My question is, why was the water cloudy? Was it harmful to the fish?  And am I doing everything right?

Any help would be great! Thank you!

Answer
Dear Krista,
*** Happy Christmas and Happy New Year 2010 *** IN ADVANCE
There are some reasons to become the tank water cloudy.
1. Gravel Residue
2. Dissolved Constituents
3. Bacterial Blossom :  White cloudiness is a result of a bacteria bloom.
Sometimes the cleaning of all filters at once, or the changing of the gravel can trigger a bacteria bloom, due to the removal of bacterial colonies that had settled on the filter media or substrate. Another cause can be aquariummedical treatment of the tank using antibiotics, which may destroy these colonies. The bacteria are either re-establishing themselves, or crowding the aquarium due to favorable conditions (poor water quality), multiplying at such a high rate that the water becomes cloudy white. Thanks. Good Luck. Honey.
* For further detail Chat (Webcam, Microphone & Typing Words), email or contact me *
a_blackwildcock@yahoo.com (TO CHAT ONLY) or parthanetra@gmail.com, Cell. No. +91 9434146179 or 00919434146179