Types of Hydroponic Lighting: What You Need To Know

Ed Wike
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Traditional Grow Lighting Systems

The HPS or high pressure sodium system is comprised of three distinct components: the bulb, the ballast, and the reflector. These three parts combined produce a total of approximately 43,000 lumens.

The ballast is the electrical component that is used to power the HID bulb. It converts the AC electricity from the outlet into DC electricity that is used by the bulb. The ballast is hung from the top of the bulb and uses a reflective device to direct the light to the plants below.

HPS bulbs range from 400 watts to 1000 watts, depending on the size and quantity of the grow area. This system is used to produce a large amount of light for a large area.

The fluorescent grow lights are made up of two components: the ballast and the bulb. The bulb is comprised of a white tube that is filled with argon gas and a tungsten filament.

The ballast and the bulb are placed into a reflective device that directs the light from the bulbs to the top of the plants. Fluorescent light fixtures come in either a cool white light or a warm white light, which is important when planning your lighting needs.

MH – Metal Halide Bulbs

One of the more popular types of lights for hydroponics are Metal Halide bulbs. The special kind of bulbs are ideal for the plants because these bulbs can help achieve optimum growth.

MH bulbs work best with the flowering and fruiting phase of growth. These lights are unique because they use a white light that gives the plants the colour they need to produce flowers and fruit. Since this light mimics the sun, it increases the length of growth and that helps with the production of flowers and fruit. These lights also have the ability to work well for several seasons. While they need to be replaced, a MH bulb has the unique ability to cease functioning when it reaches its limits.

These light are ideal for indoor plants because they provide a significant amount of light and you can manipulate the length of the light by adjusting the water levels. When the plants need more light, simply add water, and when the plant does not need as much light you can remove a little. The room temperature does not have to be higher than 70 degrees for plants to use these bulbs.

HPS – High Pressure Sodium Bulbs

One of the most popular types of grow lights is the High Pressure Sodium (HPS) system, which is used for outdoor gardening. HPS lights are comprised of a halide and a sodium bulb. They provide a light that is rich in the red and blue wavelengths of the spectrum. The red spectrum wavelengths are particularly important to plants because they help with photosynthesis, which is the process of converting sunlight into energy and producing carbon dioxide. Plant growth is stimulated by carbon dioxide, which is critical for photosynthesis, encouraging plants to grow bigger and bulkier.

The HPS system is one of the most efficient types of grow lights, but it still provides a relatively low amount of total light. The efficiency of the HPS system is because it uses only 1-10% of the energy produced to provide light for the plants. This is a big draw for people who are worried about the costs associated with lighting a greenhouse, but it is important to know that energy consumption and power bills will mount up because of the HPS grow light.

Another downside of the HPS system is that plants only need small amounts of blue light to be healthy. The HPS system provides mostly blue light, so you may notice that your plants are yellow in color. Yellowing of plants is common when using HPS lights, but it is still possible for plants to remain green using this system.

New Types of Indoor Lighting Systems

Greenhouses and indoor hydroponic gardens have always been "grow lights" dependent. Now, with LED (light emitting diode) technology and a few other interesting lighting variations, hydroponic gardening is a fascinating hobby that is also incredibly efficient and cost effective.

You may be cautious about taking the risk to buy pricey indoor lighting. However, with new advances and success comes greater acceptance and broader choices than ever before. Gardening in the dark is over! Take a look at these new types of indoor lighting systems and consider new methods for growing hydroponic and indoor gardens with plants in your own home.

Indoor lighting systems take the guesswork and danger out of indoor gardening. With the right lighting setup — a set up that is not too intense, not too low, and that gives your plants the spectrum of light they need — you can have a more fulfilling and productive window gardening season, no matter your climate or weather.


One of the most common forms of growing lighting for hydroponics are fluorescent T8/T12 lights in 18-inch fixtures. These are inexpensive and ideal for the hobbyist as well as the commercial grower. One of the few drawbacks of fluorescent T8 and T12 bulbs is that they have limited heat sink capabilities.

LED Lighting

Light Emitting Diode lighting is the newest lighting technology available and offers some very interesting possibilities for the future of hydroponics. One of the main reasons for the increased interest in LED lights is how compact they have become. They are really beginning to take off in commercial grow rooms, but are limited in home setups. This is because LEDs are still more expensive than other lights. If you are looking to get LEDs for your home setup, they are probably worth it because they don’t use much electricity, but they are expensive and need to be replaced every few years.

The other advantage to using LEDs in a grow room is they emit little to no heat. This means they can be placed directly against your plants and they don’t need any added ventilation. As you read about the other types of lighting needed for a good setup, you will notice the need for more ventilation. Most experts recommend that you add not only ventilation but a fan to help circulate fresh air through your grow room. This ventilation is needed for the other lights that you will be using, but is definitely not needed with LEDs.

Sulphur Plasma

Sulphur plasma grow lights are a popular choice among indoor gardeners who want the benefits of LED lighting. There are two prodcuts that are most commonly used: the Digital Sun and the Digital Star. The lights are called 'plasma grow lights' because the bulb includes an internal disco ball type material with millions of reflective mirrors. Many plants need blue light, which is the light most commonly used. By reflecting the blue light back upon the plant, the plant benefits from a more intense blue light.

There are several qualities to sulphur plasma grow lights that make them a popular alternative to metal halide lights. One main benefit is the amount of light a plasma grow light can put out. The LED lights come in low power, medium power, high power, and diamond power options. The most popular option is usually the medium power option which outputs 20 watts of light. It is important to know the difference between wattage and watts. Wattage refers to the power it takes to run the plasma bulb, and many of these bulbs operate on less than 20 watts of power. The actual wattage is not always an indication of the light output the fixture is putting out.