Moonlights In An Aquarium.

[lilmisshertz]

Hi everyone.
Just curious about the moonlights you can get for aquariums and other lighting.
Will this effect the fish's behavior? I've read it has positive effects but has anyone experienced problems?
Also Will other colours affect their behaviour/stress levels, such as green/red. (I've read fish are blind to red??)
I do not know much about this so if Im asking silly questions I apologise!
Please let me know what you all think on this

 

[lilmisshertz]

Just adding a picture to show you what I mean:

picture of coloured lights below:
http/www.hydor.it/images/prodotti/aqua_c.../aqua_color.jpg

 

[The-Wolf]

all my tanks have moonlights and all except one is via cold cathodes. the other one is a blue actinic florescent tube.
most fish can not see blue light, so for them it is dark and you will be able to view their nocturnal habits.

 

[andywg]

most fish can not see blue light, so for them it is dark and you will be able to view their nocturnal habits.

I must respecfully disaggree with that Wolf.

Red light is the first to be absorbed in water. At about 4-5 metres the red is absorbed by the water. By the time you are 30 metres down you only have blue light. As a result of this, most fish have far better blue vision than red.

I would say that if you really want to see nocturnal behaviour, use red lights. Most nocturnal fish in the ocean are red as they can hang around without any great fear of being seen, due to the optical deficiency of most fishes' eyes.

 

[rsands]

i just put moonlights in my tank...does make it look amazing. The fish just seem to happily swim around and do show signs of starting to "sleep" like they usually do when lights out.

 

[lilmisshertz]

Thanks for the tips you lot. So red and blue are best to use? Is green a colour they can see at all? What are the effects of putting a green light in the tank, or more than 1 light?
I'm asking this as my sister has green and red in hers.
Thanks All!!


interesting info andy!!

 

[rsands]

i have 2 lights in my tank...i have the marina ones i think it is called...very nice wee units...3 lights and the main controller cost only £24

I cant remember the different lights and their effects.

 

[lilmisshertz]

i have 2 lights in my tank...i have the marina ones i think it is called...very nice wee units...3 lights and the main controller cost only £24

I cant remember the different lights and their effects.

Do you have any pictures? And did you get the 3 lights and controller off ebay at all? I'm hoping to find a bargain

 

[rsands]

i dont have a decent picture...i will grab one later tonight when i get my camera back. only got my phone and it doesn't work really.

here is the product though: (first pic is the hub that takes up to 3lights, and the 2nd is the light flat packed! It swings right round the black bit..they look good and modern as well)

 

[Arfie]

most fish can not see blue light, so for them it is dark and you will be able to view their nocturnal habits.

I must respecfully disaggree with that Wolf.

Red light is the first to be absorbed in water. At about 4-5 metres the red is absorbed by the water. By the time you are 30 metres down you only have blue light. As a result of this, most fish have far better blue vision than red.

I would say that if you really want to see nocturnal behaviour, use red lights. Most nocturnal fish in the ocean are red as they can hang around without any great fear of being seen, due to the optical deficiency of most fishes' eyes.

What he said

Added to my recent observations of my own fish, once the tank lights were off I could just see the fish resting and fairly still. I recently added blue cold cathodes to allow me to see them after lights out and I have noticed that they are almost as active as when the main tank lights are on.

With no lights on, when I added food for the plecs the other fish didn't bother, with the cathodes on, they are all trying to get the food as it sinks.

Arfie

 

[The-Wolf]

I stand corrected, what I should've said was most bottom dwelling fish can not see blue light.

I draw you attention to this topic
http/www.fishforums.net/index.php?showto...l=visable+light
in which Bignose said the following

The question of what light is absorbed the best really depends a lot on the fish's habitat and lifestyle.

"Morphology and spectral sensitivities of retinal and extraretinal
photoreceptors in freshwater teleosts" by C. Kusmic and P. Gualtieri in Micron volume 31, p. 183-200, 2000, has a chart that shows where in the light spectrum the different absorbancy maximas are. THe chart lists like 30 species, but are broken into 4 groups:

Group 1 are strictly diurnal species that live just below the water surface or live in shallow water. Some of the species listed are the guppies and swordtails. They have maximas in the violet part of the spectrum, right at 410-415 nm, and some in the blue part 460 nm. So, these fish should be very good at picking up blue light.

Group 2 are midwater swimmers, like barbs. Most of them don't have the violet peak, but the blue peak is present in almost every species this paper looked at.

Group 3 are nocturnal species, mostly predators. Group 4 are also nocturnal bottom dweelers, like cory catfish or red tailed black sharks. These do not have the violet or blue maximas at all, only the red ones.

However, it is obvious that like a lot of life, no one blanket statement can be said about all fish, depending upon their habitat and activities, the way they detect light varies.

so, I took it from that, back in 2006, that most bottom dwelling fish can't see blue light.
did I interpret that wrongly back then?

 

[andywg]

so, I took it from that, back in 2006, that most bottom dwelling fish can't see blue light.
did I interpret that wrongly back then?

It all depends on the species.

I have read that a number of catfish do not have any cones, and as such only see in black and white.

I also know that any deep water water ocean fish have particularly good vision in the blue range as that is the only light which can penetrate that far.

However, it is interesting to note Bignose's later comment:

The maximas are the wavelengths the fish see best, but the curves are rather Gaussian (a.k.a. normal) which means that there is significant reception around the peaks. How wide the peaks are is surely species dependent, but another graph in the above paper which shows just one species' entire curve (not just the maxima) shows that there is significant overlap. That is, the curves are wide enough that there is significant reception from UV to IR. The groups 3 and 4 probably have diminished blue reception, but non-zero. Maybe zero UV compared with the other species.

The findings of the paper disagree with the reading I have done on the subject in Scott Michael's books (which are generally well referenced) and a couple of ichthyology reference books. However, these books generally deal far more with marine fish than freshwater, so perhaps there is a difference between the two.

 

[lilmisshertz]

This all gets too complicated for me, but I'm sure after reading these answers a few more times i'll get it!
So the conclusion is:
Some top, mid dwelling fish will be able to see reds more than the bottom dwelling fish, who will see more blue than red??

My next question would be, would it be best to have a light they could see in then i suppose, so the reds being shone near the top and the blue at the bottom??
Hope I'm not confusing you too much. I'm probably way off the subject here!! lol

 

[guppy_man]

I have one of the blue hydor light in my 20gal community, they aren't really that bright if you just have it pointing straight down, like that picture you posted, but if you have the light shining at an angle, it gives off a lot more light.

 

[rsands]

ye that one in picture is quite bright...i put mine in top left and top right and it shines right across the whole tank