Is Black Light Good for Aquariums?
Aquarium owners often look for novel ways to brighten up their underwater landscape.
One unique approach has been the use of black light; you often see this type of fish tank lighting used in clubs or crime scenes, yet used on a fish tank is a novel approach. It leads to one important question before you rush out and purchase one.
You can use a black light on an aquarium in tiny doses. They shouldn’t be used to heat to illuminate your tank, and a light between 315 to 380 nm and marked as UV-A should be acceptable. Lights, which are high intensity and are from a shorter wavelength, could harm everything in your tank.
What is Black Light?
Black lights are known as UV-A lights and come covered in a violet filter material. As the light from inside shines, most visible light is restricted, and all that they emit are the long-wave UV-A ultraviolet light.
Once the lights are working, they give off a violet glow, and in certain circumstances, they make things glow in the way of fluorescence, they wouldn’t normally do.
You can find the use in the medical field, hunting for minerals and as we saw clubs and artistic effects. Besides this, some variations are found in the bug zappers we see, and also sun tanning beds.
UV-A is the safest out of the three, UV-A, UV-B and UV-C. However, extended exposure can destroy vitamin A in human skin and other symptoms.
Black Light in Aquariums
One area that many aquarium owners may overlook is not so much the black light itself, but the fish tank lighting of the aquarium. Fish need their downtime, and this is the reason aquarium lights will be turned off or turned on.
A Blacklight won’t offer the same light as your regular fish tank lighting, even if they are in the safe wavelength.
A black-light can be used, though it should never be used to illuminate or heat an aquarium.
One thing to note is that there are some UV lights used as a means of sterilization. Should you use a black-light at the wrong frequency, you can harm all the healthy bacteria inside your tank. Such lights can be effective to a distance of 8-feet in all directions.
Which Fish Glow in Blacklight?
Now you know that you should only use a black light for an hour at most. Here, you can find which fish glow and have colors that pop using these lights.
Neon Tetras
The Neon tetras are one of the finest fish you can find to look at under a black light. Underneath the glare of a black light, the fish looks exceptional.
Just like their thin skin, the reflective blue stripe along their body glows, making a very special light show for any aquarium audience.
Clear substances, such as with a neon tetra’s body, also produce a fluorescent glow underneath a black light. Since neon tetras are calm fish, you can acquire them in large numbers for a satisfying black light encounter.
Platinum Angelfish
As the name suggests, platinum angelfish deliver a bright white sheen that’s ideal for black lights.
You find any black lights will react well with white, iridescent, and silvers. All of which are color traits of the platinum angelfish.
The platinum angelfish will take on an angelic appearance once you turn down the lights and illuminate your tank with your black light.
The angelfish takes on the fuzzy white dreamlike halo the black fish tank lighting induces around your fish.
Clownfish
You will find clownfish in a wide range of colors that can comprise yellow, blue, and orange that was made famous by Nemo. All clownfish feature chunky white stripes that have outlines in thin black lines, and which glow under the luminescence of a black light.
Clownfish can be highly active, so once you dim the lights, you can sit back and watch their glowing body parts create a highly unique look inside your aquarium. Your fish will clown around and leaving streaks of light that catch your eyes from every angle.
Any fish that offer semi-fluorescent colors will have colors that pop beneath black lights. When trying to decide on fish for your tank, the fish color has to be capable and suitable to absorb long-wave UV.
With this, the colors will be reflected outward, which gives you the pop. Other fish you can select are examples such as any brightly colored Queen Angelfish and Neon Yellow Tetras, among others.
Black Light vs. Actinic Lighting
Since there is a growing demand for the effects that black lights can deliver, you can find another rfish tank lighting type that may be more suitable if you worry about the health of your fish.
Here, we will take a quick look at each so you can see the difference, and then help should you decide to purchase either option.
As we saw, black light bulbs produce light in the 315 to 400 nm spectrum, and in this, it can cause our skin to tan. Below this at 200 – 280 nm is where you find the sterilization wands often used for aquarium use, to eliminate algae and disease or parasites.
Actinic lighting, when made for aquariums, produces light in the safer 420 – 460 nm range, and toward the upper end is where you see the light with a bluer color. As you move to the lower end, you see the purple hue associated with the black light.
Lighting for Aquariums (Conclusion)
When you look at these two lights, you can find both available, yet you need to use them in different ways.
It isn’t possible to use a black light lamp during the day because of the natural light in the environment. However, actinic lamps can be used during the day. Besides delivering a brighter light, humans can see this fish tank lighting source is less harmful than black light for tank elements.
It is possible to find lights that come in come as standalone units or as a combination such as the 50/50 bulbs that offer half white light and half actinic lighting.
With this, you can use the regular fish tank lighting in the day, and then switch to use the actinic side of the lamp, or if you have a black light, you can use this with the flick of a switch.
If you worry over your fish’s health, then actinic is the way to go. However, it doesn’t offer the full experience you get when you use a black light to illuminate your tank.
So long as you don’t endure your fish to overexposure, your black light shouldn’t harm your fish or anything else inside your aquarium.

Hi, my name is Adam and I’m an aquarium enthusiast! I didn’t discover the joys of being an ‘aquarium fanatic’ (as some of my friends call me!) until I was in my 20’s. When I first started out I found it difficult to find all the information I needed so I started this website to compile all the useful information I can think of. Enjoy!
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