PAR plays a crucial role in the ultimate success of your reef aquarium as light is the number one nutrient source for your corals. If there is not enough light, your corals will suffer and too much light brings the same result. A PAR meter, such as the Apogee MQ-510, can make all the difference because it allows you to measure the output and ensure your supplying exactly the right lighting conditions for the corals in your tank. 

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How Do I Know How Much Light My Corals Are Receiving?

Each aquarium is different when it comes to the amount of light your corals are receiving. Flow intensity, water quality, mounting height, light fixture spacing, rock structure, and even shadows from neighboring coral all play a role in the amount of light that penetrates into your tank. While you might be thinking your eyes can easily give you some indication of how much light is reaching your corals, the reality is our eyes are just not built to measure or "see" light in a way that can sufficiently gauge PAR.  This is exactly why a PAR meter is so critical. 

The Apogee MQ510

The MQ-510 was designed for measuring all types of lighting including LED, T5, and Metal Halide. The sensor is fully waterproof and the digital display allows you to get real-time PAR readings. The built-in immersion factor compensates for getting accurate readings underwater and, therefore, there won’t be any math or conversions required to get your results. It is designed to be a plug-n-play PAR meter, ready to go right out of the box. 

Apogee MQ-510 PAR Meter


Beyond getting real-time PAR measurements, the Apogee MQ-510 also has a few different modes that allow the user to record and store various data sets. The log mode automatically powers the meter on and off taking 60 PAR measurements, one every 30 seconds. Every 30 minutes the meter will evaluate these measurements and record the average value. The sample mode will record up to 99 separate measurements that can be taken from anywhere in your aquarium. Then, you can manually write down the measurements on a photo of your tank or, you can use the AC100 communication cable to download the measurements to a spreadsheet.

What Can I Do With These Measurements?

You can tune the output of your LED lights to achieve the conditions you desire when first setting up your tank. Once you have a set of measurements throughout your aquascape, you can position your corals appropriately based on their lighting requirements. As your tank matures, recording PAR measurements can help you see how coral growth and various other factors are affecting the light spread in your aquarium over time, ultimately indicating if/when changes are required. 

Measuring PAR using a PAR meter

What PAR Should I Aim For?

We have developed ranges based on the type of corals your keeping and their natural environment. It is critical to understand the animals in your tank and when it comes to coral, lighting is at the top of the list. Understand that your PAR measurements will never be perfect and the idea is the achieve the desired output throughout as much of the tank as possible. Choosing one or the other is going to be the easiest path to achieve success. 

  • SPS Dominant Systems: If your system has predominantly SPS corals in it, you will want to shoot for average PAR readings between 200 and 350.
  • LPS & Softies: If you are keeping a mixed reef with a plethora of LPS and softies species then, we recommend aiming for average PAR readings between 75 and 150.

This is a good time to explain the "Mixed Reef" misconception which is a common rookie mistake.  When first starting out, it is easy to believe you can achieve a true "mixed reef" housing both SPS corals on the top of your rocks and LPS and Soft corals down below. This sounds good on paper and is common advice from those looking to sell you corals that you may not be equipped for. The reality is, a mixed reef is one of the hardest types of tanks you can attempt to keep, and choosing one or the other is far more realistic when it comes to long-term success.

Once you plant your frags, they will begin to grow and the problems will soon become apparent. Not only will you run out of space with corals fighting each other, but your SPS corals on top will cast shadows on their neighboring LPS and soft corals down below, starving them of light. Alternatively, fast-growing soft corals will climb up the rocks choking out the slower-growing SPS to the same effect.

Attempting a mixed reef like this really is best reserved for those experienced enough to maintain different zones, meeting the needs of ALL the corals in their tank, and making necessary changes before problems arise. Should you attempt to keep a true mixed reef, having an MQ-510 PAR Meter on hand is all that more important, allowing you to track changes in lighting conditions over time. 

Additional Tips For The Apogee MQ510

  1. Talk to your local reef club and buy a PAR meter as a group to spread out the cost. Or, you can purchase it and make money renting it out to club members.
  2. Rinse the waterproof sensor in RO water before storing it to prevent any salt creep or other organic build-up.
  3. Get the Apogee Sensor Wand so that you can easily access all corners of your aquarium with the PAR meter. With over 40 inches of reach, it will be much easier to measure far corners and get a comprehensive snapshot of lighting conditions.