I have a tall 25 gallon tank the has been empty for the past 3 years. I was wanting ti add some fish and maybe a newt or 2 or maybe some frogs (I'm not really sure yet). I was also going to try to put in a waterfall with a little stream that went into the water part of it. I don't have to money to buy a kit that basicly does the same thing as I'm talking about. I am gonna try to make one myself. I have a pretty good idea of how to do it and I can picture it in my mind. What I really need to know is what kind of soil mixture should I use and how would I go about cleaning it once everything is in it?