Lighting can be the most important element in the growing corals.Majority reef aquariums contain corals that are photosynthetic and depend on proper illumination for their growth.Most of the symbiotic corals derive their nutrition from the products of photosynthesis. So,lighting is an important decision you need to think before you make a decision of setting up your coral reef aquarium journal.Identify which corals you are going to keep,as soon as you know what sorts of corals you intend to keep then choose the lighting that is most suitable for it.
Besides the illuminating equipment,water quality also very important,no matter how well your lighting system over your tank is,if there are yellowing agents, wastes and other dirt gathering in your water,the light source cannot reach the bottom of your tank.
There are some popular lighting system available:
T2,T5,T8 and incandescent,fluorescent,LEDs and so on.
Personally,I'd prefer the LED aquarium lighting systems,for they are more pure.We can choose a certain spectrum for our corals.

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I agree. Lighting in a SW tank is one of the most important elements. I would recommend LED or VHO at a minimum because Fluorescent was barely pushing it for my 10 gallon and 40 gallon and all I had was low light coral. Another thing about lighting was the kind of Kelvin rating of your bulbs.
Another tip is you don't have to have strong lighting hit the bottom. You can stack your live rock so you can have high light coral closer to the surface and low light coral towards the bottom.
Lighting doesnt just matter during the day, Moon lights also help your tank life act more natural. And you will see coral open their polyps at night and many actually turn into a neon color with a moon light. Just remember to give your fish atleast 4 hours of darkness before the moonlight kicks on.

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36 Gallon Saltwater reef tank
Ocellaris Clown, Scooter Dragonet, sandsifter star, Decorator crab, emerald crab, coralline snails, blue leg hermit crab, and horseshoe crab.
Zooad's and shrooms
40 pounds of Live sand, 20 pounds of LR

And there is a problem about the LEDs,they are to strong,most of them are built as powerful aquarium lighting system.Kelvin,I'd prefer 12,000K.What do think about that please?

LED or T-5. For none heat transfer. LED or Halides for the water shimmer, the others don't have that. LED's can be had with dimmers on them.

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If I'm using florescent, 12k will be good if I run two bulbs at once with a 7,5k to give the growth spectrum. but with LED it gives two colors one white and the other a form of blue and some even give off red but I havent seen it in person. One of my previous tanks I had sum ultra low light coral so I used a 20k bulb to give that deep ocean look.

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36 Gallon Saltwater reef tank
Ocellaris Clown, Scooter Dragonet, sandsifter star, Decorator crab, emerald crab, coralline snails, blue leg hermit crab, and horseshoe crab.
Zooad's and shrooms
40 pounds of Live sand, 20 pounds of LR

I am looking for dimmable LED aquarium lights,though there are some of them on the market now,I would like to wait some months until the technologies become mature.

Red light source in LED aquarium lights for growing corals? Oh,,I have not seen it before,and I don't think it is necessary...

Its out there and its mature. There are a ton of people using this now.

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The red LED's are for color rendering.

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Yes,I see,Red LEDs will increase lots of PAR value,but they are not good for a tank,especially when the Red light source penetrates the water,the tank looks not pure,I don't like...Only Blue and White are good for tank....

I am agree with you.The LED aquarium light is very useful.The most important is LED Aquarium can save more energy.

its amazing how aquarium technology is keeping up with our modern world =)

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36 Gallon Saltwater reef tank
Ocellaris Clown, Scooter Dragonet, sandsifter star, Decorator crab, emerald crab, coralline snails, blue leg hermit crab, and horseshoe crab.
Zooad's and shrooms
40 pounds of Live sand, 20 pounds of LR

When you see the units with RED LED's in them, you will note that there are only about 3-5 in the unit, just enough for rendering, nothing else.

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You might be right,but most of our experiment prove that the Red and Orange spectrum will be filtered out by the water immediately,they cannot penetrate the water.

Interesting, never heard that one. Thanks

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I thinks the power of the lighting system depends on how deep is your tank !

What? I have never heard about that the depth of a tank will affect the lighting power.
Definitely no.

Absolutely, depth has a great impact on the lighting. The deeper the tank the stronger the light needs to be. 18-24" 3watt LED or 175w halides will do. Deeper than that, and your corals should be kept higher in the rock work, or you should get stronger halides and LED's for the bottom.

LED Aquarium Lights,*Lighting; emitters, PAR, DIY, How they work | Aquarium Article Digest
Aquarium Lighting; Reef, Planted Light Information. PAR, Bulb, Watt, Kelvin, Nanometers, MH, LED.
samsreef.com - PAR readings - How much light?

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100% correct to a point. Depends on what corals you plan on keeping in there also.

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[quote=Reefing Madness;158275]Absolutely, depth has a great impact on the lighting. The deeper the tank the stronger the light needs to be. 18-24" 3watt LED or 175w halides will do. Deeper than that, and your corals should be kept higher in the rock work, or you should get stronger halides and LED's for the bottom.QUOTE]

That's right, but my LED light has far more penetration and PAR value than any others I have ever seen. Here is the parameter and PAR(based on 120 degree optical lens,White 14000K:Blue 460nm=2:1 ratio):

12 inch:112,300 lux,1280mmol;coverage:0.8 square meters.
20 inch:78,000 lux, 728mmoll;coverage:1.12square meters.
30 inch :46,000 lux, 265mmol; coverage:1.28square meters.
40 inch: 18,900 lux,206mmol; coverage: 1.76square meters.