Aquarium Lighting

[CRUSHER]

LED is not necessarily any more efficient if its white, but if the light is for plants, white isnt actually necessary (although it's probably desirable when humans are watching), therefore lumens are also only relevant within the context of colour.
The most efficient type of white lighting is still, by far, ceramic metal halide, but it is unreasonable unless your tank is around 8,000 litres and cylindrical for starters. For smaller projects, it's still a saw off between white LED and fluorescent.
If you're big into plants, but aren't watching your aquarium 16 hours a day, a mix of red and blue LED lights will keep both your plants and your power bill extremely happy and your fish content. Plants don't really have much use for green light, which is why they are green. While fluorescent only produces white light regardless, the big energy savings with LED only come with producing light in the colours plants want (red and blue) Of course for vane and picky humans, very few want to look at an aquarium unless it uses white light.

COPIED AND PASTED !

[tizzite]

Interesting! Where did you get this?

I made an LED light fixture that I originally intended for a reef setup, so I put 50/50 white and blues into the light.

I ended up using it for a moss/java fern tank, and dimmed the blues so it would look a little whiter. I'm glad my blue and red LEDs aren't going to waste!

[Totenkampf]

I was researching this recently once I had decided to try something different this time around in my planted tanks. I went with T5HO as it is inexpensive and efficient. Until the hobby comes up with a better rule of thumb than the watts per gallon method or PAR meters become more commonplace then lighting is still a game of trial and error. If you have a very large planted aquarium, then you can get very good results from MH since they are by far more intense per watt than flourescents but the tradeoff is space and heat. They also are a very direct beam of light so they dont get good coverage, IMO.