I am just now starting to purchase my equipment for my tank. I recently got the tank which is a 75 gallon glass aquarium. I have the stand and now im just focusing on the filtration unit i want to install. I went to the local pet shop and asked for ideas, they told me to just use liverock as the bio filter and a sump for the mechanical and chemical. I had already began to plan a trickle but from what they told me liverock will do exactly what the bioballs would. I was wondering what kind of filter i should use for my tank. If your suggestions are DIY's please give me tips on the building instructions.