The Deep Dive on Reef Aquarium Lighting, Part 2: Lighting Technologies

I get asked fairly often what light is the best light. Unfortunately, there is no right answer. First off, there is the difference in aesthetics. That is a purely subjective decision that only hobbyists can make for themselves. Most of the time hobbyists gravitate towards the blue end of the spectrum because it is very flattering to corals that fluoresce brightly.In terms of coral biology, the type of lighting that will work the best for your tank will depend a great deal on what animals you intend to keep. As I mentioned in Part 1, corals will adapt to lighting by regulating their zooxanthellae, so most coral will grow under any of these lighting technologies. Having said that, it is also entirely possible to have some corals take on a desirable appearance while other corals become less attractive under the same light. Such is the price to be paid for a mixed reef tank

The Deep Dive on Reef Aquarium Lighting, Part 1: Zooxanthellae, Color Temperature, and Light Intensity

LEDs continue to gain a loyal following as a capable reef lighting technologyLighting is important because it directly affects how we visually enjoy the hobby and, more importantly, the vast majority of the corals in our tanks are photosynthetic. In this two-part article, we will first cover some of the basics of the light itself and then discuss the various lighting technologies people use to light their reefs. Coral and zooxanthellaeCoral as we know it is a symbiotic relationship between the coral animal and dinoflagellates called zooxanthellae. Zooxanthellae live in the tissue of the coral and are like algae in that they contain chlorophyll for photosynthesis. The byproducts of photosynthesis are things like simple sugars that the coral hosts can use as an energy source. It is for this reason that coral are often described to the layperson as having traits of both plants and animals. The color of zooxanthellae is varying degrees of brown. However, there are over 80 known varieties of zooxanthellae

Salty Q&A: Is My Lionfish Going Blind?

Bright aquarium lighting is sometimes implicated in causing blindness, especially in lionfish (Pterois spp.)QuestionI have a volitans lionfish that’s been in my 200-gallon tank for over two years, and lately it has begun to act like it can’t see. At feeding times, it makes an effort to grab food that’s drifting by but usually misses—like it can tell that food is in the water but can’t see it well enough to get it in its mouth. Is there a way to tell if this fish is actually going blind versus having some other health problem? – Submitted by Sean Myles Answer Thanks for your question, Sean! In his book The Salt Smart Guide to Preventing, Diagnosing, and Treating Diseases of Marine Fishes, Jay Hemdal addresses the issue of blindness in fish—specifically the subtle symptomatic differences between a fish that is going blind and one that is actually ill to the point of becoming moribund. Here is that particular excerpt from his book, which I think will answer your question better than I can: Blindness A very common symptom reported by home aquarists is that one of their fish has become blind. This, more often than not, is a result of a fish becoming ill to the point that it is moribund (close to death) and is not just blind. Basically, a fish that bumps around the aquarium, runs into the tank sides, and ignores food may not be blind at all; it may just be dying

Salty Q&A: Bay Window Reef Lighting?

Sunlight passing through a window generally provides very directional, odd angle lightingQuestionI’m setting up my first reef aquarium and want to keep my approach as natural as possible. The room where I plan to place the tank has a really big bay window in it, and succulents and other sun-loving houseplants really thrive there. Is there any reason I can’t take advantage of all that natural sunlight for my corals instead of using crazy expensive artificial lights?” – Submitted by CZ Answer Though you would save a bundle if such a plan were feasible, I would discourage relying on window lighting to illuminate your reef system for several reasons. First, the amount of sunlight passing through the window is going to change throughout the year as the sun’s position shifts and the days get longer or shorter with the seasons. That won’t bode well for tropical corals, which demand 10 to 12 hours of direct sunlight per day. Second, the sunlight passing through the window will reach the tank at an odd angle and from only one direction. So even if you could get enough sunlight of sufficient intensity to pass through the window and onto your tank on a consistent, year-round basis, your light-hungry inverts would always be shaded on one side. Third, placing an aquarium too close to a window—especially one that lets in a lot of direct sunlight at certain times of year—can make it difficult to maintain a stable, appropriate water temperature, which is stressful to the inhabitants