Amuro, if you plan to cycle without fish, here's a great article on it. Many of us routinely cycle new tanks without exposing fish to toxic ammonia and nitrite, and we'd be happy to hold your hand if you decide to go that route.
http://www.aaquaria.com/aquasource/cycle2.shtml
As long as I'm at it, I'll share my thoughts on cloudiness. First of all, the color can give you a clue as to what the problem is. If it's a green-tinted cloudiness, the problem is most likely a bloom of unicellular algae.
If the cloudiness is white, it could be either particulates (like dust from your gravel) or microorganisms. Usually, if particulates are going to cloud your water, it will happen immediately and slowly disappear (over a week or so). If the cloudiness develops over the course of some time, it generally means there is an abundance of some of the normal microorganisms that inhabit our tank. There are lots of these critters, and they feed on each other, so if one populations grows quicker than another, you get a bloom that makes the water look cloudy.
Please note that these microbes are NOT the same ones that we refer to as the beneficial bacteria that oxidize ammonia and nitrite. Therefore, you can have a white-water outbreak that has no bearing on the tank's cycle. Often, the cloudiness occurs early in a tank's life, so it's easy to think that it's related to the cycle, but it's independent. I've had fully cycled tanks that, for some reason, developed cloudiness but suffered no loss of the biofilter.
If you have white water that seems to fit the description of a microorganism bloom, the best treatment is to do nothing. It will go away. You can change the water, but you'll just reduce the number of organisms in the water column, and they'll quickly reproduce and the cloudiness will return. You really just need to wait for the populations of organisms to come into balance and all will clear up.
Hope this is helpful... don't be afraid to come back and let us know if you need assistance with cycling questions.
Jim
