is there are difference?

[joelb]

is there a difference between a plant metal halide bulb and an aquatic mh bulb?

[Jonthefishguy]

Kelvin rating. 6500k is a yellow tint which is good for plant growth. Plants do not grow well under any other kelvin rating other than 65k to 67k. The following colors are good for all coral depending on whether they are deep or shallow species. 10k is a crisp white, 14k is a crisp white/blue hint. 0 to 30 ft ocean depth color. 20k is a crisp blue tint 31 to 60 ft ocean depth color. The actual colors vary depending on manufacture bulbs.

[ErikH]

yes, one is for plants. (see thread where you say "oh pick meeeee, it's a coral.") lol...

[joelb]

good one, i deserved that

[Ping]

I thought Plant bulbs are in the 5500 range?

I run 65K's on my reef.

[hobogato]

lots of people use the lower K bulbs for rapid growth and suppliment with lots of actinic to make the corals produce the proteins that protect them and make them more colorful.

[subsailor]

Kelvin temperature

is an astronomical term that has been adapted to characterize

aquarium lighting. Sometimes you will see Kelvin referred to as Color temperature.
Lights with a Kelvin temperature range of 5,000 to 6,500K is referred to as white lighting and are only useful for freshwater aquariums. Reef lighting generally runs from 6,500 K to 20,000 K. A 6,000 K light best mimics the noon sun, but generally a 10,000 K light gives a more pleasing light to humans. The 12,000 to 20,000 K lamps are known as cool lights and highlight the phosphorescence in many corals.

3000 K yellowish - Warm lighting
6000 K noon sun
10000 K white with blue
20000 K blue – Cool lighting

This was pulled from this article
http://www.easttnreefclub.com/Lighti...20Aquarium.pdf