When building a reef aquarium, you will find an endless variety of products and components available. For beginning hobbyists, this can be both intimidating and confusing. Sometimes products prove to be very useful, making time spent maintaining your reef much easier. Other times products can be misleading, mislabeled or simply not right for you.

Today we are outlining a list of the key products that will make your reef keeping experience a success. We hope to provide you with enough detail to make choosing the right products easy (although you can always contact us for free one-on-one support). Keep in mind this is not a complete list of all the equipment you'll need. We are focusing on the components that will help you succeed in the reefing side of the hobby.

Must-Have Equipment for a Reef Aquarium:

  • Sufficient lighting
  • Quality protein skimmer
  • Refractometer and thermometer
  • Calcium and Alkalinity test kits and additives
  • RO/DI system
  • Appropriate powerheads

Sufficient Lighting

Properly lighting your reef is one of the most important things you can do. Many of the corals available in our hobby rely on photosynthesis to survive. Having ample light for these specimens is so important that standard output aquarium lights will not do the job. Recreating the natural environment of your corals is the ultimate goal and ample lighting proves to be a key factor for success.

Among the types of lights available today, you will notice fluorescent T5, metal halide and LED lighting taking the lead. Within the fluorescent style of lighting, you may also come across T12 (VHO) and compact fluorescent lights. If you decided to go with fluorescents, T5 technology is the smartest choice for building a reef tank today.

Flourescent T5 is becoming the favorite fluorescent option because they run cool, are energy efficient and have excellent output. There are also so many options for bulbs you can create infinite color combinations. These lights are great for reef tanks that measure 24" or less in height. You will want to choose a 4, 6 or 8 bulb fixture that covers the entire footprint of your tank. Some hobbyists even use 10 and 12 bulb fixtures—it really all depends on the dimensions of your tank. But to reiterate, choose a fixture that covers your entire aquarium. For example, a 48" long x 13" wide tank should will need a 4 or 6 bulb T5 fixture to provide ample light throughout the entire tank. That will also give you the widest options for coral selection.

Metal halide is classically the most successful light for a full mixed reef tank. Metal halide is a type of HID (High Intensity Discharge) light that provides very intense output. It will give you a beautiful natural shimmer in your aquarium, much like sunlight shinning into the ocean. These lights utilize high amounts of electricity and run very hot. You must therefore consider the increased energy costs associated with these types of lights before you purchase them since you may also have to incorporate some sort of cooling system (fans and/or a chiller).

Metal halide is excellent for large and/or deep aquariums. The intensity of output will give you the best light penetration compared to other types of lighting. We generally recommend one 250 watt bulb for every two square feet of aquarium space. Anything deeper than 24" should utilize 400 watt bulbs for the best results throughout the entire water column. For hexagon and other odd-shaped tanks, metal halide is the best way to provide ample light because you get such great light spread, especially when combined with an appropriate reflector.

The latest technology used to illuminate aquariums is LED (light-emitting diode). The benefits of LED are that you get excellent output with very minimal electricity consumption and virtually no heat transfer. The downside is the technology is expensive and does not provide the wide variety of colors you can achieve with fluorescent or metal halide combinations. Although the technology is relatively new to the aquarium hobby, many hobbyists are already experiencing great success. Plus the money you'll save on electricity bills can be tremendous.

Be careful when choosing an LED fixture. Many of the fixtures currently available may not be strong enough to sustain the aquarium inhabitants you intend to keep. I generally recommend LED fixtures for aquariums that are 24" or less in height to ensure you'll have enough light to reach the bottom. The light spread on LED fixtures can be very directional, so it's important to ensure you get one that covers the whole tank to avoid shadowing or dark spots. Manufacturers usually list sizing guidelines for common tank dimensions in their product descriptions. Just be certain the LED fixture you're purchasing is designed for a reef tank. If you aren't sure, contact us!

Quality Protein Skimmer

Having a good protein skimmer will help keep your water clean and free of organic waste. It will also help the gas exchange (oxygen levels) in your tank. There are many skimmers on the market. Choosing a quality unit is enormously beneficial. I cannot stress this enough: buying quality equipment up front will go a long way toward helping you achieve success throughout the life of your reef tank.

Look for units that have favorable reviews and/or good word-of-mouth from experienced hobbyists, like us. Generally speaking, anything priced under $100 probably isn't going to last very long. Acrylic construction and high-quality pumps will help ensure a long lifespan. Avoid multi-function skimmers that offer mechanical and/or chemical filtration along with protein skimming.

Over sizing your skimmer is always a good idea. In my experience, many manufacturers advertise inaccurate tank size recommendations. That's why I cut their recommendations in half. For example, if a manufacturer states their skimmer is rated for tanks 60-100 gallons, I would only recommend that skimmer for a tank that is 50 gallons. You want the skimmer to cycle your entire tank volume 1-3 times an hour. Look at the pump size and water flow through rate to help determine if the skimmer is right for you.

You also need to choose a style of skimmer that is appropriate for your tank. There are hang-on, submersible and external protein skimmers available, so it is important to consider the mounting style before buying anything. You may need to measure your aquarium or sump before you shop. Having these dimensions in mind and knowing what space you have available to mount the skimmer will help to ensure you choose the right model.

The technology used to produce foam varies from skimmer to skimmer. The most common method of producing foam is a Venturi style skimmer. Often these types of units advertise a "needle wheel" or "pin wheel" impeller that will help increase foam production. Becket style, spray injection and down draft technologies each have their own benefits. Although not all styles will be available in all sizes, it is still wise to consider and compare their unique attributes before buying.

Refractometer and Thermometer

Proper water parameters are critical in reef aquaria. Using reliable testing equipment helps ensure you're making decisions based on accurate test results. Basic parameters, like salinity and temperature, can be difficult to maintain, even for the most advanced hobbyist.

You will notice a few instruments available for testing salinity, including floating hydrometers, precision refractometers and electronic monitors. We recommend refractometers over the classic floating hydrometers and electronic monitors for a few reasons. Floating hydrometers may be inaccurate after the first use and can be hard to read. Electronic monitors are expensive and sometime difficult to maintain. Frequent calibration and proper storage are necessary for most electronic monitors.

Precision refractometers utilize a crystal prism and ample light source to measure salinity levels based on light refraction through your tank water. They are easy-to-read and provide consistently accurate results with minimal maintenance. For ease of use and reliable results, refractometers are your best option for any marine tank.

Thermometers are essential for monitoring aquarium temperature. Most thermometers these days are digital, although many of the classic alcohol thermometers are still available for just a few dollars. I personally keep a digital thermometer in my tank at all times for constant monitoring. I test the accuracy every so often by comparing it with a classic alcohol thermometer to ensure my digital readings are correct. With this method of testing, you can be certain that your temperature is accurate and take whatever steps are necessary to avoid fluctuations throughout the day.

Calcium and Alkalinity - Testing and Supplementation

Reef aquariums are very dynamic: no two are ever the same due to ever-changing water parameters. The need for supplementation of certain elements will therefore change on a tank-to-tank basis. Sometimes, depending on the types of coral and stocking level, an aquarium must be supplemented for sustained growth and success. Calcium and alkalinity are the two most common elements used by corals on a daily basis. The only way to find out if you need to supplement your aquarium is to test the water. Many local fish stores offer this service but testing at home helps ensure accurate results and quality control.

For a new hobbyist, I highly recommend a calcium and alkalinity test kit. Most kits come with easy-to-read instructions and are simple to use. Testing will let you know how much your tank is using and how much you need to supplement. It is wise to test these parameters regularly. When calcium and alkalinity are out of whack, it can sometimes be confusing and difficult to correct.

To maintain these parameters, two-part alkalinity and calcium solutions are your easiest option. They are pre-diluted into a liquid form which makes them easy to dose into your aquarium. Many two-part calcium and alkalinity supplements include major and minor trace elements in the exact ratio found in the ocean. This ensures these elements are present in your aquarium at the proper ratio at all times in addition to maintaining calcium and alkalinity. Additional supplementation may not even be necessary if you're regularly dosing a two-part solution combined with weekly water changes.

Some hobbyists argue that you are essentially "paying for water" when you buy liquid supplements. This is true to some extent. Of course, most powdered supplements require you to dissolve them before adding them to the tank. This creates an extra step every time you need to dose, which is often daily for well-stocked reef tanks. Personally, I prefer the easy route of measuring the liquid and pouring right into my tank. Most of us don't have metric scales or weighing devices that are often required to properly utilize powdered supplements. Liquid two-part supplements are much easier to use. If you use a powdered supplement, be sure to dissolve it completely before dosing your tank.

RO/DI Water Filter

An RO/DI unit may be the single most overlooked piece of equipment for reef aquariums. Dedicated hobbyists know that a RO/DI tap water filter installed at home makes the hobby much more enjoyable. RO stands for Reverse Osmosis and DI stands for De-Ionization (learn more terminology in our aquarium glossary). When working together, these two types of filtration will provide you with 99.9% pure fresh water that should measure 0 total dissolved solids.

This pure or RO/DI water has a number of benefits for your marine reef aquarium. It will avoid unnecessary introduction of harmful metals, chlorine and other elements into your tank. You will not get extra phosphate, silicate or nitrate build-up in the aquarium, reducing the risk of nuisance algae. You will be able to properly mix saltwater and safely top-off your aquarium with water that is easily accessible at home, instead of making repeated trips to your local fish store. For these reasons, RO/DI units are strongly recommended.

You will notice different brands and styles online but most of them will provide the same functionality. For reef aquariums, we always recommend a RO/DI system over RO. This ensures the most pure water possible, as the extra de-ionization stage produces water that is free of any unwanted elements.

There are a couple of key features to look for when choosing an RO/DI unit. A "Purity Monitor" or "TDS Meter" provides you with the total dissolved solids reading. This TDS measurement helps you know when to replace your filter cartridges and ensures proper function of the unit. Many, but not all, RO/DI units have them included so keep any eye out for this. You may also notice some units have a pressure gauge. This is used to monitor the pressure inside the unit so you'll know if it's functioning properly along with the cleanliness of the main TFC filter.

The most expensive units on the market typically include a booster pump. Booster pumps help increase and maintain constant water pressure into the membrane. This is useful when water pressure is below the minimum required water pressure of 45 P.S.I. or to increase your product-to-waste water ratio. All RO/DI units will have a certain level of waste water that is concentrated with removed impurities. Wasting water is not the best practice so you might try using this water in your garden, laundry, simple household cleaning, etc.

Appropriate Powerheads

Submersible water pumps are commonly referred to as "powerheads." Powerheads help to maintain water movement in your reef tank so that it will resemble natural conditions. Powerheads also increase gas exchange and keep debris suspended for easy removal with your filter. Powerheads are commonly available in two different styles: classic jet and propeller.

The classic jet stream pumps produce a very directional, laminar type water flow in your aquarium. These pumps have the impeller housed inside a volute that directs the water output. These pumps are great for moving water in one particular area such as behind or around rockwork or aquascapes. Some examples would be the Aquarium Systems Maxi-Jet or Taam RIO powerheads. They work great with classic wave timers for nutrient export purposes.

When positioning powerheads inside your aquarium, be sure you have flow reaching into every corner of the tank. Low flow areas, known as "dead spots," cause nutrient build-up that ultimately results in increased algae growth. You should also be mindful of the flow requirements of your corals so you can position them (or your powerhead) accordingly. Your rockwork and aquascape may dictate how you can arrange your powerhead(s). Just be sure to position them carefully so you can circulate 5-10 times your aquarium water volume per hour.

The newer and more popular propeller-type powerheads produce a wider type of water flow. These powerheads are generally used to move water to the open areas in your tank creating a natural, gentle flow that is suitable for reef fish and corals alike.

Many powerheads now offer brand-specific controllers that will work to give you variable outputs, wave making capabilities, feed hold and night modes. Compared to the classic powerheads, these controllable units are much more feature-rich and will help you create much more lifelike living conditions for your reef inhabitants. The most popular controllable units come from TunzeEcoTech Marine and Hydor.

The flow rates for these pumps can be misleading, so be careful when sizing the pumps. I usually recommend movement around 10-20 times your tank volume per hour, sometimes higher for SPS dominant reef tanks. The same rules apply for positioning these pumps: be are sure to take into account your rockwork and coral placement.

With some basic knowledge, the right equipment and regular testing, I am certain your reef keeping will become easier, more enjoyable and even more successful.