I know this may be a newbe kind of question but I need to ask it anyway. I have a 33 gallon fresh water tank. How often should I change the water and how much?

This is my question too ! i will be thankfull anybody answer it !

that depends on the tank you have. I have an 80 gallon, it's planted, I ues ferts & CO2. I change 50% of my water weekly to keep things in ballance. If you have a smaller tank with plastic plants and not so many fish you can get away with changing 30 - 50%, every other week. With a high population of fish I'd say change 30 - 50% weekly. Because I change the water weekly in my planted tank I change 50% in my other tanks as well. May as well do them all while I have the python out. The fish seem to like it, they are looking good and eat really well.