Soon i am going to be getting a 20g fish tank and i am unsure how to cycle it i have read the article but still don't understand, what is the point in doing it? Do i do water changes while the tank is cycling? Please help!
If you're fishless cycling, you don't have to do water changes, if you have fish in, then the water changes help reduce the concentration of the nitrogenous waste (ammonia, nitrites and nitrates), giving the fish a better chance of surviving.
As long as your concentrations can still support the growth of bacteria, you don't need to change water.
So that I don't go down the wrong path in answering, which bit do you need help with, the bit about the cycle, what it is etc, or which method to use to cycle?
I have moved your thread to the Nitrogen Cycle section of the forum to help you to receive more responses.
The nitrogen cycle keeps your fish safe from ammonia poisoning, or to prevent your fish from swimming in their own waste.
The fish produce ammonia which over a period of several weeks turns into nitrites. Then the nitrites turn into nitrates. The ammonia levels and nitrites disappear and you should have some trace (under 20) of nitrates. At this point your tank is cycled and your fish should be safe as long as you keep up with frequent water changes and tank maintenance.
Cycled readings are 0 ammonia, 0 nitrites and under 20 nitrates.