You’re probably confused about which grow light to choose for your aquaponics system. It’s quite a detailed subject that can warrant its own book. For now, I’ll provide a brief explanation of what considerations need to be made when selecting a grow light.
When Are Grow Lights Needed?
The need for grow lighting all really depends on your circumstances in terms of:
- Climate – You might live in a country that doesn’t have much sun.
- Space – Perhaps you don’t have a garden where you can grow your plants outside.
If either of those apply to you, then you’ll likely have to resort to setting up your aquaponics systems somewhere indoors such as a spare room or garage. If that’s the case, that means your plants won’t be getting any direct natural sunlight, so a grow light is essential.
Grow Light Spectrum
So which grow light do you need? There are a few different types of them each with their own advantages and disadvantages, but to understand the purpose of a grow light, you need to take a look at its light spectrum. Here’s a graph detailing that.
What does this colorful diagram mean?
- White Light – This is directly in the middle between 500 to 600nm. This represents the sun in what is known as solar light, and is what’s considered to be a full spectrum.
- Blue Light – Necessary for your plant’s green foliage stage.
- Red Light – Necessary for when your plants begin fruiting.
- Visible Light – This is what we as human beings can actually see, in what is also known as ‘PAR’ (Photosynthetic Active Radiation). PAR is the most important section on the light spectrum chart because this is what your plants will need.
It’s better to use a grow light that aims for the PAR light spectrum since you’re likely going to be growing a variety of different plants, as opposed to using blue or red spectrum bulbs that are suited for specific plants at certain stages of growth.
Grow Light Intensity & Efficiency
After you’ve got the light spectrum decided upon, you need to focus on the intensity or power of the grow light, which is measured in lumens. A lumen is also known as ‘foot candle’ which is basically how bright the light is when placed one foot away from the source (in this case, your plants).
1 lumen = 1 foot-candle falling on one square foot of area.
You’ll need a grow light with a PAR spectrum combined with plenty of lumens shining down onto your plants in order to provide them with the light they need to grow properly.
The energy efficiency of a grow light is also important as the more efficient it is, the less power will be lost due to heat generation from the light fixture itself. This means that every ounce of power is directed at your plants in the right way. As a result, your electricity bill will also be cheaper which leads me to my next point.
Cost Of Grow Lights
You’ll want to spend your money wisely as grow lights can be expensive, and you also want to make sure that the light fixture you purchase has enough power for your plants to grow.
In terms of costs, you have to think about:
- Upfront Cost – How much does it cost to purchase the grow light?
- Maintenance Cost – How much does it cost for a bulb replacement when your existing bulb has reached the end of its life?
- Ongoing Cost – How much does it cost for you to run the light fixture? No matter what type of grow light you buy whether it’s LED, fluorescent or HID, you want to aim for around 25 watts per sq. foot otherwise it may not be powerful enough.
Once you’ve figured out these costs, you can have a bit more peace of mind knowing that you’re not breaking the bank with the lighting bill.
To get the most out of your aquaponics system, I highly recommend the following articles, where you can decide from the highest rated and bestselling products for aquaponics.