what colour light to use for plants 14000k?

[Guest gros21]

ok i have spare metal hallide ballist here set up ready to go, i want my plants to go crzy esspically my java moss

\my Metall hallide is 400w so id prefer to use that is taht over kill on a 3ft tank

[Bettarazzi]

I think you might get a lot of algae with that much light. I know a plant farm up north that grows plants outdoors but uses 90% shade cloth. So only allowing 10% of daylight to come through. But I'm not sure how strong daylight is compared to aquarium lights or metal halides. One way of counteracting algae growth is to put the lights on a timer but instead of turning them on continuously for 10 hours, do it in 2-3 hours spurts. So on for 2 hours, off for 1 hours. The reason is algae takes a while to register that light is available where plants can use that light immediately. So although the lights may be on for 10 hours in total, the algae can only use it for part of time.

[splendidbetta]

Are you sure about the algae photosynthesis part Razzi? Everything happens much the same at a cellular level. If anything algae would be more efficient since it is rarely many cells thick, so photons penetrate the cell easier. Also, since algae usually don't have an intracellular storage system, they would be metabolizing and therefore photosynthesizing almost constantly.

[Bettarazzi]

I read it in a magazine I think. I'm looking for the reference. Or maybe it was something I saw on the web somewhere which will be harder to find. I used that method to control an algae outbreak in one of my tanks.

[brettc777]

Don’t worry about all that techno mumbo jumbo, just throw in 200 BN catfish! Algae problem solved! Haha

Then your next issue will be Bio Load, that's easily fixed by doing constant water changes

Then your next issue is slipping a disc in your back from doing so many water changes, that's easily fixed by spinal surgery

Then your next problem is paying for the spinal surgery, that's easily fixed by going back to work and working 60 hours a week

Then your next problem is stress from working so much.... I better stop this could go on forever! Who knew metal halide lights were such a problem hahaha

[Daniel]

14,000k will be inaccessable for plant photosynthesis, the wavelength cannot be used by the chlorophyll. try something instead between 5,200k-10,000k

[Guest Carla]

Full sun is around 6000K or so. These bulbs may be sold as cool white. The T8 flouro's 6400K can be purchased at Bunnings for $5.00. They are just moving into the blue part of the spectrum. Plants do fine with these.

10000 K is well and truly into the blue. It simulates deep water light. Coral utilizes this range.

You can also get special plant lights that give off light in the red part of the spectrum and in the blue, but are stingy on the yellow in the middle. That is because plants use red and blue but algae loves yellow. These are made for aquariums and cost more.

I don't know if this type of bulb is available in metal halide. That is one type of lighting I skipped over in my lighting research.

Carla