Filter Questions and Lighting

Question
Filters:
In the books that I have read so far they mostly suggest an air filter, but I'm confused, when I see tanks on YouTube or pictures of saltwater tanks I do not see any air bubbles throughout out the tank why is this? Would I need an air pump if I'm using 2 Powerheads a canister filter and protein skimmer? (Those are things I plan on using) and also for the protein skimmer and Powerheads I'm a little confused if I need pumps with them or if they are self driven or have the pumps built into them.

Lighting: I've read up on lighting fixtures such as PC, Florescent, and Metal Halide in the books you have recommended for me, but I haven't heard anything about LED lights, and I was browsing the Internet and came across the LED lighting fixtures, they have LED lights that simulate daytime, and then Moonlit LED's. Have you had any experience with either types of LED's?

Answer
Hi Jake. You do not need an air pump. Is your book old?(Ha Ha) The amount of equipment you are planning on using is plenty for your tank. You want to make sure the surface tension of your water is being broken up to have a better gas exchange between the air and your water. You also want to make sure you have good circulation of water around your tank. Not too turbulent but moving. Your powerheads are simply devices that move water. They keep the flow of water up and can be placed in areas where the water is not moving to prevent stale water areas. They just plug in and go! As for the protein skimmer it will depend on what kind you go with. Most of them come with a powerhead or water pump that has airline tubing attached to it to pull the air into a chamber where it mixes with the water and causes a foam(this is called the venturi skimmer). This foam collects the dissolved organic waste and pushes it up into a collection cup. Some protein skimmers are driven by an air pump but these are not as efficient nor are they as consistent as the other ones.
LED light fixtures for lighting a reef tank are some of the newer types of lighting out there. They are highly efficient in the output of light, run cool so you don't need a cooling fan like you do for metal halides, and they are great at conserving energy. The only problem is that in order for there to be light output in the right range for a reef tank there needs to be a lot of them and they can run you an arm and a leg. I mean like $1,000 for one that will fit a 36 inch tank. These will support soft corals and plantlife but are not quite enough for any stony corals. If you have the money and aren't planning on doing any stony corals go for it! They have a very nice shimmering effect like the metal halides without the heat and the bulbs life is much longer!