Adam Blundell M.S.
Lighting questions will never be solved. Hobbyists will discuss this and debate it forever. If you want to see the data and analyze the graphs then please review the works of two of my great friends Sanjay Joshi and Dana Riddle. Sanjay has produced more spectral plots, reflector reviews, and PAR readings than you could ever read. From the biological end Dana has analyzed photo-inhibition and coral photosynthesis to a new level. Now, lets talk about preference!
Shown here a vendor uses identical plastic corals to show the different colors produced by different bulbs. This is a great way for a hobbyist to see what colors and intensities are produced by different bulbs.
â€œWhat lights should I buy?â€
I hear that question all the time.
â€œWhat lights do you use on your tank?â€
Yep, I get that all the time as well.
What Do You Want?
Iâ€™ve learned to ask that key question. It took years before I figured this out, but better late than never. Iâ€™m frequently asked â€œwhat light should I buy?â€ and I now reply â€œwhat light do you want?â€ When people ask me what kind of lights they should buy, they really just want me to answer with the lights they want, or what they just so happened to recently purchase. I guess validation is the answer.
One, Two, Three, Four, what are we fighting for?
Lighting a reef tank provides a sliding scale for how many bulbs are needed. For some reason this is a huge topic in the hobby that warrants lots of conversation (a nice way of saying arguing).
The Two Bulb Duo
For years and years the hobby has been dominated by a two bulb (color) system. The top selling lighting fixtures of today are just like they were 15 years ago. You need a while bulb, and a blue bulb. It is a 10 K halide with supplemental actinic fluorescents. It is a daylight bulb and an Actinic 03. It is 14 hours of blue light and 8 hours of white light. It is the staple of aquarium lighting. These systems are seen everywhere!
The Two Bulb System
Incorporates actinic and white light
Aesthetics for sunrise/sunset actinics
Commonly available and widely used
Limited number of bulb options
Bulb is on or off, no in between
Aesthetics for sunrise/sunset actinics Cost of several bulbs
This Aquatic & Terrestrial Research tank is shown just after being set up. It uses a Current-USA fixture with white lights (halides) and blue lights (T5).
Even the newest of fixtures being made today are using the same white/blue lighting system that has been in the hobby for decades.
One Bulb Does It All
On the far end of the spectrum a philosophy exists where one type of bulb does it all. This is the 14 K halide or the 20 K halide. It is the pendant fixture. This philosophy says pick an overall color you like and get a bulb to match it. One bulb, thatâ€™s all. This system is growing in popularity. Two tanks come to mind when I think of this 1) Marzena Blundell (my wife) who used the one bulb system on her 150 gallon reef wall aquarium and 2) Sanjay Joshi who used this system on his personal 500 gallon reef pillar system. Both of these tanks were designed to use one large metal halide to spread light over a large area. By one bulb, we really mean one type of bulb, not necessarily one individual bulb. The idea here is to put a bulb every four feet or so and just use that one type of light. The light comes onâ€¦. stays on all dayâ€¦ then goes off at night. It is very energy efficient, clean looking, and simple.
One Bulb System
Color matched to specific look
Cost of only one bulb
Space saving and versatile
On or off, no in between for lights
Aesthetics lacks the sunrise/sunset
Limited on color options
Coralife has produced some very popular lights for the one bulb system. These pendants are intended to be a one source light for the reef aquaria.
A clip on light is perfect for those corner aquariums, such as used on this classy suspended nano reef.
Marzena Blundell’s 150 gallon reef wall system is lit by only 14K halides. The lights are either on or off, nothing in between.
Multiple Bulb Selection
Imagine lighting your tank with 500 led bulbs. Would you use 250 white bulbs and 250 blue bulbs? Maybe 200 white, 150 blue, 5 orange, 13 red, 17 green, 11 purple, and 104 yellow. Maybe you would move those led bulbs around to put specific colors over specific corals. Maybe you would cluster leds into bright areas of light and leave spaces for dim areas void of light. This is the future of reef aquarium lighting.
One bulb for every need philosophy is used in stage lights for rock concerts, multiple VHO fluorescent bulb set-ups, and various common fluorescent tubes are available for this need.
Multiple Bulb System
Ability to select exact colors and placement
Versatile to each user
Dimmable, Controllable, Programmable
Costly to buy many bulbs
Small bulbs lack intensity of larger bulbs
Lack of availability
A product vendor shows off the ability for color changing lights. These systems can be made to create specific colors to match the hobbyist’s preference.
Some led fixtures, like this one shown here, actually contain microchips that can be programmed for dimming effects and specific lighting times and intensities.
The PFO line of led lights has brough leds to the average hobbyist. You can now buy an led system right off the shelf.
Interchangeable leds allow a hobbyist to specifically design the exact colors they prefer.
Last but not leastâ€¦ well actually yes the least, weâ€™ll now cover no bulbs! This odd off-topic could be made into an entire article (hey that gives me an idea). All I want to introduce the reader to at this point is that not all reef creatures need light. Sometimes a very attractive aquarium can be made without light loving animals. Iâ€™ve been quite impressed with some recent aquariums Iâ€™ve seen that used cheap standard lighting, as the light was not important to the tank.
No Bulb Necessary
Super-duper cheap and easy
Very useful in species specific small tanks
Used in large predatory (aggressive) tanks
Limited to a very few coral options
Lack of aesthetic intensity
Lack of aesthetic colors
Some rather beautiful and interesting animals have no specific lighting needs.
This simple aquarium features a cheap built in light.
However it does make for one of the most unusual and interesting tanks I’ve seen, a tank full of feather duster worms.
Ask yourself what you want! Learn how complex or how simple lighting systems can be. The home hobbyist has many options for lighting reef aquaria. Whether you will use several bulbs, a few bulbs, or one bulb, you can have a very successful reef tank. While many things change in this hobby, one thing is for certainâ€¦ lighting options will always grow to confuse the consumer with multiple options.
Adam Blundell M.S. is a hobbyist, lecturer, author, teacher, and research biologist. Adam works for the University of Utah in Pathology and in Marine Biology. He currently helps run the Wasatch Marine Aquarium Society, of which he is a former president. Adam is also the director of the Aquatic & Terrestrial Research Team, a group which bridges the gap between hobbyists and scientists. Adam can be reached at his author forum.
Â© Blundell 2008