Ok, so im new to the hobby and have a question, I have a 2x2x2 60g cube and a 125g tank, both are currently collecting dust. My wife wanted to set one up as a project we can do together. I don't have all the money required to to set up a reef so I am going to do a FO in the cube. I understand lighting in a FO is for visual aesthetic purposes but as far as live sand do i need to use it to help with filtration or not? Also what is the best way to clean a tank to get it ready to fill?