kelvin rating question

i have a few extra 400 halieds laying around.. the only thing is they are 20k radium bulbs... does anyone know what kelvin ratings are okay for veg growth? and if a 20k bulb would cause slow growth or defects at all?

nocturnalreef said:

i have a few extra 400 halieds laying around.. the only thing is they are 20k radium bulbs... does anyone know what kelvin ratings are okay for veg growth? and if a 20k bulb would cause slow growth or defects at all?

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are you sure its 20k? 6500k is best for veg, 2700k for flower, but i never heard of 20, but i'm not a pro.

It's a reef aquarium bulb. Will work fine for veg if you have nothing else.

https://www.rollitup.org/general-marijuana-growing/723-things-know-about-lighting.html


Click on the above link

burninjay said:

It's a reef aquarium bulb. Will work fine for veg if you have nothing else.

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And it's 20k??

Heres a graph of it's spectrum output. Will stimulate photosynthesis if you don't have another bulb, but a MH in the 5000k range would be better.

20k aquarium lights are the norm....

Indoor Don said:

And it's 20k??

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20k Kelvin, as in 20,000k

yeah it's a reef bulb it's actually a 20k radium.. not just a 20k.. the radium is a CRAZY blue mixed with a purpleish hue.. my ballast runs 2- 400 --20k radiums, -----any halied and HPS so i can do whatever but i had the bulbs sitting here and i have an idividual 20k radium ballast that is sitting also so i figured why not... but i didn't want it to just work.... i wanted it to be a good grow bulb...

yes 20000 Kelvins, just google '20000 kelvin bulbs' if you dont believe it!

I read a thread once of a guy who vegged with the 20k, and had another grow beside with a normal 6,500 rating, and the 20k grew a bit faster.

jnuggs said:

I read a thread once of a guy who vegged with the 20k, and had another grow beside with a normal 6,500 rating, and the 20k grew a bit faster.

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i bet no idea if it was on this site or not do you? if you can remeber the site or find a link to it i would appreciate it... i was actually going to run a 20k and a hortilux blue eye in the same area as a dual mix thing and that thread would be great.. i just wanted to make sure i didn't screw up their growth or make them go south in anyway.

does anyone know if i put a halied and a hps to mix colors would that enhance growth in anyway with the 3500k and hortilux blue mixed light? i run a dual 400 ballast that runs anything( as said before) so i just wanted to see if there are any good color mixes with two bulbs to speed or enhance growth

bumb this thread. I'm curious also. I'm going to have a 250watt MH system with 20k kelvin bulb, and 2 96w T5 flouro's.


Will this work well for veg?

i meant bump