Although that last post was very informative, it may have been a little misleading. A skimmer and LR are both a must if you are trying to simulate the ocean ecosystem. A skimmer uses microbubbles to attach to the protein in the water and extracting it into a cup that is emptied on a regular basis. LR is rock with living organisms and bacteria colonies that naturally break down harmul chemicals and detrius in the tank. You can also add a HOB (Hang On Back) filter, canister filter or an overflow to a sump/fuge or wet/dry system. To learn more about these systems, search the boards on what is right for your setup.
As for water circulation, you will need to add multiple powerheads to your tank to help circulate water. In order for the LR to work correctly, you will need adequate water flow over it and no dead spots (standing water) in the tank.
