Red light

[Dfrashid]

So I heard leaving the red light on at night will show some pretty cool things in my aquarium at night but I also hear this will cause algea to grow crazy please what are your thoughts good or bad? Fyi I have a radion xr15 4th gen

 

[Floyd-]

I use a small pen light with red light to view the tank at night.

 

[Dfrashid]

I use a small pen light with red light to view the tank at night.

Does it cause algea to grown ? Also I have a radion XR15 4th Gen light

 

[AFHokie]

Does it cause algea to grown ? Also I have a radion XR15 4th Gen light

I think he/she means they just use it to see things when they want to look. It's not constantly on.

 

[Dfrashid]

I think he/she means they just use it to see things when they want to look. It's not constantly on.

So it's not a good idea to leave it on all night?

 

[gsepanik]

I would avoid leaving a light on at night as it may affect the photoperiod of your corals.

 

[AFHokie]

So it's not a good idea to leave it on all night?

I can't point you to a scientific study but I would say no. We use red as a "night light" because it has a minimal impact on our night vision and does not travel as far so its safer in a military setting. The reason map lights and internal aircraft lighting is red when we are blacked out.

But that is all based on the human eye, not what marine organisms perceive and/or absorb. Red light is used differently by coral and algae so it's very likely it will have some impact on them.

With the exception of moonlight the ocean gets dark at night so we should try and mimic that cycle in our reef tanks. I've read several accounts of people leaving their lights on 24/7 and the resulting ill effects.

 

[Floyd-]

So it's not a good idea to leave it on all night?

I wouldnt. I just use the redlight to inspect things at night as needed.

 

[Uncle99]

So I heard leaving the red light on at night will show some pretty cool things in my aquarium at night but I also hear this will cause algea to grow crazy please what are your thoughts good or bad? Fyi I have a radion xr15 4th gen

I light my macro algae with red.
Corals need to “rest” from their photosynthetic process.
Lights out.

If your talking flashlight to look, fine.

 

[Dfrashid]

I light my macro algae with red.
Corals need to “rest” from their photosynthetic process.
Lights out.

If your talking flashlight to look, fine.

Thank you for all your help and useful information I thank everyone who posted

 

[vetteguy53081]

So I heard leaving the red light on at night will show some pretty cool things in my aquarium at night but I also hear this will cause algea to grow crazy please what are your thoughts good or bad? Fyi I have a radion xr15 4th gen

Red light promotes algae and is recommended for chaeto growth. On tank lighting 3-6% is safe range

 

[damsels are not mean]

Red light promotes algae and is recommended for chaeto growth. On tank lighting 3-6% is safe range

I don't agree. I've never seen any evidence that red light encourages algae in any meaningful way, at least not compared to any other band of light.

So I heard leaving the red light on at night will show some pretty cool things in my aquarium at night but I also hear this will cause algea to grow crazy please what are your thoughts good or bad? Fyi I have a radion xr15 4th gen

The small amount of light you'd need to see stuff in the tank at night, especially with other lights in the room off, is not enough to cause any measurable impact in algae growth. If the fish all go to sleep and corals close as normal that tells you it's dark enough to be night time to them.

 

[vetteguy53081]

I don't agree. I've never seen any evidence that red light encourages algae in any meaningful way, at least not compared to any other band of light.



The small amount of light you'd need to see stuff in the tank at night, especially with other lights in the room off, is not enough to cause any measurable impact in algae growth. If the fish all go to sleep and corals close as normal that tells you it's dark enough to be night time to them.

with red light, there are studies that suggest that red light can cause photoinhibition in coral especially those like Lepto and similar. Mention also made by Dana Riddle who is a lighting pro of effects. Corals need red and green light spectrum for zooxanthellae but not a constant flow.
Running Orpheks for several years, I have seen firsthand the effect od reds at 10% versus 4% and the higher value showed algae mainly in my overflows. Now theyre clear

From Dana Riddle:

These are two papers from over 30 years ago examining spectral composition and coral photophysiology:

Kinzie, R.A., P.L. Jokiel and R. York, 1984. Effects of light of altered spectral composition on coral zooxanthellae associations and on zooxanthellae in vitro. Mar. Biol., 78:239-248.

Kinzie, R.A. and T. Hunter, 1987. Effect of light quality on photosynthesis of the reef coral Montipora verrucosa. Mar. Biol., 94: 95-109.

In a nutshell, red light was found to regulate zooxanthellate density/chlorophyll content. In extreme cases, large amounts of red light bleached corals.

I did similar work in corals and LEDs in 2001 and 2002. Again, red light *potentially* causes coral bleaching:
http://www.advancedaquarist.com/2003/11/aafeature
Later work showed red light can be harmful (Wijgerde):
http://www.advancedaquarist.com/blog/scientific-evidence-that-spectrum-matters-for-coral-growth
So, if you're ramping up red channels to show off the colors of your clownfishes, are you seeing any negative effects on corals?