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actinic. why?

i'm curious about the importance of actinic.

based on my reading, it simulates the lower water column lighting from the natural sun light where the depth of the water filters out all of the larger wavelength light (warmer, yellow and red colors) and leaves only the blue.

If you use 10K or 20K or a wide spectrum of light/color temp, it include some of the blue light in the composite radiated light. why then do we as hobbyists use actinic alone at separate time intervals?

help? it's just for my understanding. thx

jay
 

mnat

Officer Emeritus
Staff member
Moderator
A lot of people use it to simulate dawn and dusk patterns to give more natural lighting to the reef. Others use it because of the color pop it gives to corals. The old logic was that 10k and whiter bulbs were for growth and 20k or bluer bulbs were for looks. While this still holds mostly true, I have seen some tanks first hand that had nothing less than a 14k bulb and had amazing growth.
 
oh i see. i remember some previous threads about color pop vs. growth.

i see then. actinic is used for color enhancment primarily.

thanks alot!!!
 
The fact that it actually does actually help in coral colours/fluorescence is highly debatable. It does make your tank and the corals within differently coloured for sure. I use 3 blue bulbs (ATI BLue Plus) to supplement my 6500K MH which I use for growth. If you use a bluer primary light, you might be able to do away with actinics.

However the tank does look very good under blue bulbs and there might some connection between the blue bulbs and coraline algae .

If I remember correctly, Vangvace had posted once that some light expert/manufacturer in the last Macna had said that if you have full spectrum lighting, all the other colour tubes are almost purely for our vanity.

Check out the thread named where the members enlist what they learnt at Macna XXI.
 
My corals are a lot more vibrant with the actinics. Had 20k's but it wasn't close to what the actinics do for growth
 
is it true if you are a stony coral in shallower reefs.... in the wild the natural sunlight will be full spectrum including blues but not filtering out the other colors.

whereas, if you are a soft octocoral in deeper reefs, you will get more of the filtered bluer light?

are we not always striving to provide what the nature provides to our marine friends?
 
I believe color is the primary reason for them, but it is easy to argue that certain corals and coraline algae do better under actinics too.

With enough blue and purple spectrum bulbs corals especially the LPS give me flashbacks to the black light days, now all I need is a Led Zepplin poster next to the tank. ;D
 
reeferwanabe said:
with the tv on and the sound off.
I'm looking to do away with my actinics by going to 12k

IMHO 12K is not blue enough..I think, maybe you remember Mike is running 14K, which might do it.
 
I don't run actinics on my 200+ gallon system. I miss the way they make the corals look, but everything is colorful and happy!
 
First of all, the look, under actinics some corals, zoos and macro just glow. I do the dawn and dusk cycle, I feel its more natural then just blasting them with full spectrum.
NJ_ychung1, I have the 50-50 bulbs in one tank and I am very disappointed in them, just my opinion.
On the flip side I have read that for max growth, 10,000k bulbs work best, then I followed a thread on RC that had a guy growing out zoos under pure actinics and his results were positive.
GregH
 
Nickjr000 said:
My corals are a lot more vibrant with the actinics. Had 20k's but it wasn't close to what the actinics do for growth
I'm a moron and I meant COLOR... The 20k looked real blue but not like actinics. All the neons pop way more with them
 
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