Black Light And Fish

[DarkShadow435]

So, I've been researching blacklights because I want to put one in my custom lighting unit for my 55 dwarf cichlid tank. I've found some very contradicting information.

I found that one website i looked on stated that blacklights that are built by using a regular fluorescent light and adding a special coating to it are completely safe.

I also found this on another forum archive.

black light works to reflect ultra violet .. what you see when you're dancing at the club is the reflected ultraviolet of fabric whitener. do your fish wear shirts that have been washed in detergent containing 'whiteners'?

lastly and mosst importantly .. UV light can/will damage your eyes and there is research to show that certain kinds of UV can damage a fishes eye as well.

As well as this from the same topic.

blacklights are not dangerous to fish. They have no more UV output than any other bulb. They just have output only in that range.

And I have also found the sight for "Glofish", which are zebra danios which have been genetically mutated to help diagnose water pollution problems. They say that using a blacklight for night time viewing will make their colors glow. However, it says nothing about hurting his fish.

My boss and I got into the discussion, and we wondered about the fishes eyes. If the UV radiation would hurt their eyes, or cause problems with them, or their bodies. I know that UV radiation causes skin cancer in humans and other large animals. I didn't know if water filtered out the radiation, or what the "deal" was.

So this brings my question. Does anyone have any more information for me? It would be VERY helpful.

 

[Starfishpower]

hey thats a pretty good question! iv got a 50 gal. im getting ready to set up and i was thinking about making it a night tank... filling it with nocturnal only fish and having some kind of moon light type thing. ill ask my biology professor next time i have class and get back with you on this

 

[DarkShadow435]

well, if you want a beautiful moon light, i have used the cold cathode meathod, and it works GREAT! i've installed it on three tanks so far, and i cant stress how beautiful it looks at night.

 

[waterdrop]

To quote a couple of wikipedia paragraphs...

"While "black lights" do produce light in the UV range, their spectrum is confined to the longwave UVA region. UVA is considered the safest of the three spectrums of UV light. It is the higher energy (shortwave) light in the UVB and UVC range that is responsible for the DNA damage that leads to skin cancer. UVA light is much lower in energy and does not cause sunburn. UVA is capable of causing damage to collagen fibers, so it does have the potential to accelerate skin aging and cause wrinkles. UVA can also destroy vitamin A in the skin.

UVA light can cause DNA damage, but not directly like UVB and UVC, it does so indirectly by producing reactive chemical intermediates, such as hydroxyl and oxygen radicals, which in turn can damage DNA. The strength of a black light in comparison to sunlight is minuscule, so it is doubtful that UVA light poses any significant health risks. The weak output of black lights should not cause DNA damage or cellular mutations the way sunlight can."

~~waterdrop~~

 

[Colin_T]

Don't touch the black lights. They are trouble with a capital UV & A. Fish don't have eyelids and as such they can develop cataracts when exposed to UV light.
If you want a night light then get a bluemoon or actinic light. They are a blue light that will allow you to see the fish at night but won't cause you or your fish any harm. The blue moon lights were originally designed for catfish tanks.

 

[three-fingers]

Don't touch the black lights. They are trouble with a capital UV & A. Fish don't have eyelids and as such they can develop cataracts when exposed to UV light.
If you want a night light then get a bluemoon or actinic light. They are a blue light that will allow you to see the fish at night but won't cause you or your fish any harm. The blue moon lights were originally designed for catfish tanks.

But after reading the above, how can you say that? If the light from the tubes isn't going to be as bad as what fish would get from the sun anyway and some amount of the UVA is bound to be reflected by the water and even more wont penetrate very deep, I doubt it's going to do any major harm.

However I wouldn't use one on an aquarium...it's hardly natural for there to be that much UVA at night, and as you say fish don't have eyelids so it may keep them awake (especially if if whatever species it is can see well in that spectrum) just as much as a strong blue light would.

Blue lights look great (and eventually I think I'll get one), and are fine if turned down very low - but the fish can still see it and while it seems natural to us, how often do you think shallow ponds/river get that much moonlight shining on them?

The best lights are the red ones, since I've read here many times that fish cannot see the red spectrum as well, so to them it's like being in darkness. I ussume it's the same as with reptiles, and that's why you get red heat lamps for vivariums.

 

[Colin_T]

But after reading the above, how can you say that? If the light from the tubes isn't going to be as bad as what fish would get from the sun anyway and some amount of the UVA is bound to be reflected by the water and even more wont penetrate very deep, I doubt it's going to do any major harm.

The best lights are the red ones, since I've read here many times that fish cannot see the red spectrum as well, so to them it's like being in darkness. I ussume it's the same as with reptiles, and that's why you get red heat lamps for vivariums.

Although it is true that wild fish get plenty of sunlight consisting of various UV wavelengths, they can hide under logs or plants and very few are found in water as shallow as a fish tank. Some are but most aren't. During the middle of the day many fish take refuge in the deeper water or under shelter.
Having a UV light on a tank is a bit like having a UV light on in your room. It just isn't necessary. Save your money and buy something safer and more useful.

The red heat lamps in vivariums are to provide heat for the reptiles. Some reptiles have UV lights as well. Usually the desert dwellers. They have a UV light to help them develop vitamin D. They aren't on all the time tho, maybe a couple of hours a day. And the reptile can move around its enclosure and avoid the light if it wants to.

 

[T1KARMANN]

why gamble with your fishes eye sight would you gamble with yours

 

[Colin_T]

get em some Polaroid sunnies
big round ones like the supermodels wear

 

[T1KARMANN]

get em some Polaroid sunnies
big round ones like the supermodels wear

then they can put them on top of their heads when the lights are off looking cool

 

[Colin_T]

add a mirror ball and the UV light can shine off that making it look like a club. Get groovy little fishies. And all that weed in the tank for them to get down on.

 

[three-fingers]

Although it is true that wild fish get plenty of sunlight consisting of various UV wavelengths, they can hide under logs or plants and very few are found in water as shallow as a fish tank. Some are but most aren't. During the middle of the day many fish take refuge in the deeper water or under shelter.
The red heat lamps in vivariums are to provide heat for the reptiles. Some reptiles have UV lights as well. Usually the desert dwellers. They have a UV light to help them develop vitamin D. They aren't on all the time tho, maybe a couple of hours a day. And the reptile can move around its enclosure and avoid the light if it wants to.

Fish should be able to escape it in our aquariums just as reptiles should be able to escape it in vivarium's. Fish should always really have some sort of cover even from regular aquarium light tubes (which do produce some UVA as well). Lot's of reef tanks have multiple UVA tubes over them to bring out colour and I believe some corals may even need it. Putting a UVA tube over an aquarium for day time use is very unlikely to cause harm and is more natural for lot's of fish, for night time use it may look cool, but it would be very unnatural for the fish.

I'm just just trying to emphasise the suitability of red lights for night use compared to blue or UV lights, I know what the red lights are for .

UVA and B are very important to lots reptiles, UV sources should be on all of the day time rather than just a couple of hours...to provide heat and/or UV as close as to how the sun would in nature. The UVB is important for the vitamin D synthesis, but the UVA as we're talking about here is important for other things, in general reptiles can see this spectrum well and it effects their behaviour significantly.

 

[Starfishpower]

get em some Polaroid sunnies
big round ones like the supermodels wear

then they can put them on top of their heads when the lights are off looking cool

"I wear my sunglasses at night So I can so I can Watch you live and breathe your storylines

(And) I wear my sunglasses at night So I can so I can Keep track of the visions in my eyes"

dont 80's songs just rock B)

 

[DarkShadow435]

Ok, i do know about blue moon lights and actinic bulbs, since i mentioned them in a previous post. However, i was just trying to gather information. I currently have a blue moonlight made from cold cathodes. And i've decided that i do not want to put a blacklight on, but i am curious what the effects would be. So no need to get into heated debates over it. lol

 

[Colin_T]

"I wear my sunglasses at night So I can so I can Watch you live and breathe your storylines
(And) I wear my sunglasses at night So I can so I can Keep track of the visions in my eyes"
dont 80's songs just rock B)

Cory Hart from recollection