How to Choose a Lighting System for Your Aquarium

Aquarium lighting is one of those controversial aquarium subjects that tend to confuse new hobbyists. There are loads of conflicting opinions out there (and everybody’s right, of course). The Custom SeaLife® lighting systems we sell are backed by years of public and private aquarium research and positive results. After all, it’s results that count, and naturally we would be thrilled if you ordered your lighting from us.

However, because we have the best interests (and pocketbook) of the average aquarium hobbyist at heart, we recommend that you look at the subject carefully, and make your decision of which lighting system to purchase based on scientific fact rather than hype. The lighting for your new reef or live-plant aquarium is one of the most expensive investments you will make. When selecting a lighting system for your aquarium, do a little research and carefully consider these questions to help you make your decision:

What animals (or algae/plants) are you planning to keep, and what are their lighting requirements?
We strongly recommend you design your aquarium around the aquatic life you intend to house instead of setting up your system and learning by trial-and-error. Marine aquatic life (and all life for that matter) is too valuable a resource to waste. Read some books and learn from the mistakes of others, ourselves and other so-called experts included.

The standard rule-of-thumb for selecting lighting systems for reef aquaria, is 3 to 5 watts of light per gallon. This range is typically defined as 3 watts being suitable for most soft corals and anemones, and 5 watts being ideal for almost all stony and hard corals. The taller an aquarium, the more wattage is required. This standardized rule, while technically inaccurate, works in most cases except one, and that is when the aquarium exceeds 24" to 30" in height. If your tank is a tall model, you should consider using more lighting.

What type of aquarium are you planning?
If you are setting up a fish-only aquarium, there is usually little need to invest in anything more than standard fluorescent aquarium lighting. Additional light will only result in additional algae growth and hours of work to keep the aquarium clean. Be careful, however, not to assume that fish do not require a good artificial light source with the proper spectrum in order to survive. They do. Always use bulbs designed for aquarium use, and if your aquarium is 24 inches high or taller, consider using more than one bulb across the length of your tank. Don’t use cool-white bulbs! There are good reasons why they cost less!

How much will it cost? This includes not only the initial cost of the light system, but also the cost of bulb-replacement and operating (electrical) cost. Some lighting systems may cost less initially, but may require frequent bulb changes in order to maintain the intensity and spectrum of light being produced. Check the manufacturer’s recommendations for bulb-replacement and then get on the web and see what other hobbyists have to say. (Good rule-of-thumb — people who want your money may tend to exaggerate!).

What is the temperature of the room where the aquarium will be kept?
A metal halide lighting system may seem like the best way to go, but you don’t want to find out later that you’ll need an expensive chiller when your tank temperature exceeds 80 degrees! A good rule is to add 3 to 4 degrees (Fahrenheit) to the average room temperature to determine the potential water temperature. For aquariums equipped with metal halide lighting, you may want to use 7 to 8 degrees as a guide. If you like your home on the warm side, and you’re planning a live-reef aquarium that will house hard corals or other sensitive species, make sure you’re prepared to make an investment in a chiller. If you cannot make that investment, plan the livestock of the aquarium by selecting shallow-water species that can tolerate higher daytime temperatures. But be careful! There are very few sessile invertebrates that can survive sustained temperatures that exceed 85 degrees by day, and many fish become stressed by wide fluctuations in temperature from day to night after the lights go out.

How much clearance do you have above the aquarium?
Do you have the room above the tank to use that huge metal halide system? Most metal halide and VHO systems (including those we sell) now come with a UV resistant shield that protects the aquarium from harmful UV radiation when the fixture is directly above the water surface. This shield also protects the hot lamps from moisture. If your lighting system is a retrofit type however, it may not include a shield. Retrofit systems are designed to be mounted several inches above the water surface, usually inside a canopy top. VHO systems should be mounted about six inches from the water. Non-fan-cooled metal halides without a light shield should be at least eight (and preferably twelve) inches above the surface of the water.

Are you planning to build your own lighting system?
Unless you have a good working knowledge of electricity, and how to properly moisture-proof and ventilate light enclosures, WE STRONGLY RECOMMEND THAT YOU DON’T BUILD YOUR OWN LIGHTING SYSTEM! Nearly all deaths attributed to working with aquariums are caused by electrocution. Water is an excellent conductor of electricity. Saltwater is one of the best conductors of electricity. We personally know of two deaths caused by electrocution due to home-made lighting systems. In both cases, metal fluorescent shop-lights were to blame. Think of the money you’ll save, yes! Then think of what your life is worth. Want to save money or just get creative? Build your own filter, but BUY your lighting system!

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