Blue light to white light ratio

[SombreroBen]

What should my ratio of blue to white light be? Right now it's 50/50 for 2 hours in the morning and night but 100% white during the day.

 

[TheBear78]

Hi.
It depends on whether you are trying to grow coral, if you are trying to control algae growth and also how you want your tank to look.
I have mine at 50% (power) blue and 10% white from 10 am to 8 pm but ramping up and down for an additional hour each end. I have white low to reduce algae growth but im.happy.with the look.
My ReefLED lights generally only allow adjustment of a preset blue and white channel although I can modify that if I'm really fussy.

 

[mdb_talon]

I personally prefer blue to ramp up for a couple hours to about 90% intensity and stay there for 5-6hrs hours then slowly ramp down for a couple hours. I usually just have white come on during a peak period for about 4-5 hours in the middle of the day, but even then I have white at half the intensity of blue.

Not saying that is the "right" way to do it just giving example of what I do. The correct way to do it is largely dependent on the tank, which lights you have, and personal preference.

 

[Lavey29]

If you are running 100% white during the day you will need an underwater lawn mower.

 

[Spare time]

So, blue light will be more efficient per the "par" value. Meaning that it likely takes less to hit the max intensity a coral can take under blue vs the mixture that is "white" light. Blue light also stimulates calcification independent of photosynthesis. So in other words, blue is the powerhouse. The other colors can be used by zooxanthellae but not as efficiently.

BUT, no one ever considers the fish. I believe that there should be a healthy wide spectrum over the tank for the fish. I am not a fan of only blue anymore due to this. The percentage is up to you, but consider both of these. Note that white light will not be promoting more algae. Algae is not limited by light in a reef aquarium. If it is, then you can't grow coral as coral needs algae (zooxanthellae) to survive.

 

[SombreroBen]

Hi.
It depends on whether you are trying to grow coral, if you are trying to control algae growth and also how you want your tank to look.
I have mine at 50% (power) blue and 10% white from 10 am to 8 pm but ramping up and down for an additional hour each end. I have white low to reduce algae growth but im.happy.with the look.
My ReefLED lights generally only allow adjustment of a preset blue and white channel although I can modify that if I'm really fussy.

so does the white light or blue light produce more algae? Because I heard it was the blue light.

 

[Spare time]

so does the white light or blue light produce more algae? Because I heard it was the blue light.

Possibly blue light 9it depends on the species of algae), but really algae isn't limited by light in a properly lit reef tank. Algae is limited by predation

 

[Goodersgold]

Whilst I appreciate that "what works for me" may not necessarily work for you, I'm running the LED50 over my Max Nano at the suggested height and I'm sure I'm loosing soft corals I think due to too much light, what hadn't occurred to me was the dose of light I am giving, my LFS advised that I should run the blue at 70% and whites around 20%, but for how long...yes I know the 12 hour cycle, ramp up ramp down etc, but surely that's not what happens on a real reef? The sun's intensity is varied. I'm going to try this, I'd be interested in what you think.