Bulb K rating

[MarcusCarcus71]

first off Im new.

I am buying a dual 400 watt retro kit, I have to buy bulbs, just curious about the different K rating and how it effects coral.

I am just going to use 1 400 for my 65 gallon tank with a coralife 36 inch PC fixture with a 96 watt actinic.

any links or info would be appreciated.

Thanks, Marcus

 

[Anonymous]

That's actually a fairly big question. I'll give my nickel version but try some searchs on "Sanjay". He's done quite a bit of research on reef lighting.

$0.05

Corals will generally adapt to whatever color (K rating) you throw at them.

Generally, the lower the K the more useful light for the corals.

My bottom line is to find what color your prefer to look at and then ask the folks here which bulb they recommend for that color.

Personally I like 10,000K supplemented by VHO Actinics. Your tastes may be different.

 

[Anonymous]

basically what guy says

lower kelvin = yellower bulbs.. higher kelvin = bluer bulbs

Now because it's easier to make yellow light 6500k & 10000k bulbs tend to have much higher PAR values (how much actual light energy there is) than 13000k-20000k bulbs.

That being said, it does become a large matter of preference since bluer bulbs tend to make colors look nicer, it doesn't emphasize "dirty" tank areas (browns and yellows aren't as clear), and depending how blue you go you can often get fluorescense that you just don't see with lower kelvin bulbs.

To give you an idea of what to buy, well that's preference, I would suggest looking at various colors and letting that give you an idea.

Since we're throwing our preference in... I personally like the 14000k with 10000k pc/t5s to whiten up the blue a bit.

 

[MarcusCarcus71]

thanks for the help.


I wasnt sure if it mattered to the corals.

 

[Anonymous]

Anybody use 15K XM's?

Pics?

Very blue?

 

[petey]

I just got a pair of 15k xm 250's yesterday. They look pretty good, although i think ill have to get something to replace my 2 super actnic VHO's to turn down the blue a bit. Ill get a pic when I get home.

 

[Anonymous]

I'm looking for less blue. 10K's it is then.

Thanks

 

[Anonymous]

10k will be no blue

 

[Anonymous]

I just tried the 10k xm DE it was pure white, very bright, so I am sending the bulbs back to hello lights and they are swapping me for 20k. Hopefully those will be better. I like a good mix, but with the 10k so brilliant white, I figured the 15k wouldn't be enough either so I am trying the 20k. I will let you know friday and can post some pics of those then.

 

[Bojangles]

Right now I'm using 10k / 460 actinic combos and my tank is alittle blue for my taste. I actually added a HO 48" florasun t-8 fixture to add alittle of the lower pink/red spectrum.

My question is this. If I ditch the actinics and go with 10000k / 6700k would I get the more natural sunlight look?

Anyone have this combo?

 

[Anonymous]

I have two 40w actinics on it with 20K xm's....too blue IMHO. So I think I'll go for the 10k's w 40w actinics and I may even change the actinics to those URI 12K bulbs(the pinkish ones).

I saw a post elsewhere by GShiemer where he said he is very disappointed with the 15K xm's. Very weak and minimal growth.

 

[Anonymous]

Do you have a pic of your tank that I can see as far as the 20K's? Are they DE or SE?

 

[Anonymous]

My question is this. If I ditch the actinics and go with 10000k / 6700k would I get the more natural sunlight look?

Anyone have this combo?

I have that look on an algae tank. 10,000K is tolerable but 6700K makes everything look washed out.

 

[Anonymous]

The 20K XM's are mogul on my tank.

Click on the pics to enlarge:

 

[Anonymous]

OK those are waaaay bluer than what the 20k HQI 250w I have. I have them up and running this morning and they are gorgeous IMO. They are no where near that blue. Right now I have them about 10 inches above the tank until I figure out how hot they run and then I will probably drop them a few inches, but aside from that I love the color. I will try to get a color close shot of it later today.

 

[Anonymous]

here are the shots so far.