In my tank I just have the run of the mill blue rock, it is getting rough looking and some of it is turning white, which I am sure is not a good thing. Anyways, is changing it just as easy as taking out the old and putting in the new or is there a special way to do it. Also, what is everyones opinion on the best stuff to use (without spending a ton of money). I do have live plants if that matters. I have seen a fair amount of people using some kind of sand. What are the pros and cons of different types? thanks!