The Best Grow Lights for Your Hydroponics System

Grow lights are an important integral part of any hydroponic system. There are a variety of different types of light systems available on the market, so care must be made when you choose which type of grow light to use with your own hydroponics system.

The increasing diversity and variety of lights and the different types of lighting systems available for growers only serve to increase the potential confusion that already exists. This article seeks to clarify everything relating to this subject, and so help you reach decisions about which types of lights are best for your own circumstances.

What are the Best Grow Lights for Hydroponics?

Of the many types, sizes, shapes and varieties of grow lights that may be used on your hydroponics system, the three main categories are fluorescent, high-intensity discharge (HID) and light-emitting diode (LED). There are advantages and disadvantages for each type. So let’s go through these in more detail.

Fluorescent grow lights. This type of grow light is the most popular among hydroponic growers because of its relatively low cost and efficiency.

Of the fluorescent grow light type there are two subsets, and these are compact fluorescent light (CFL) and tube-style light.

Compact Fluorescent Lights (CFL). CFLs are relatively inexpensive bulbs that can be very versatile in their shape. CFLs are a good choice for the smaller hydroponic installation because they don’t heat up to a great extent and therefore they can safely be put right next to your plants.

Tube-Style Fluorescent. Tube-style fluorescent lights are available in several different specific types. The most popular, or at least the most numerous, are the T5, the T8 and the T12; of these, the T5 are certainly the most popular type because of their efficiency relative to the other types. Tube-style fluorescent lights are considerably wider than their CFL counterparts and they are generally arranged in parallel rather than in series and are mounted on a sturdy fixed board.

High-Intensity Discharge Grow Lights (HID). HID lights are more efficient than fluorescent lights, it is generally thought. But they release a bit more heat than fluorescent lights, and for this reason, they will heat up in a short space of time and they will need continual ventilation. Of this variety, there are three sub-varieties:

High-Pressure Sodium Lights (HPS). HPS lights give off reds and yellows on the whole colour spectrum. Because of this, HPS grow lights are used more often during the fruiting and flowering stages of plants. Though they can be used quite happily throughout any plant’s life cycle.

Metal Halide Lights (MH). These emit light within the blue range of the spectrum. Because of this, MH lights are suited most often for the vegetative stages in the life cycle of plants.

Ceramic Metal Halide Lights (CMH). These appear to be similar to MH grow lights on first seeing them. However, CMH lights have a considerably broader colour spectrum range than both the MH and HPS types, and they last longer than both of the other two types of light as well.

Light Emitting Diodes (LED). LED grow lights are very efficient in comparison with all the other types of light; LEDs emit a large amount of light while only needing very little electricity to do their job. They are extremely lightweight and do not emit much heat. Many LED-type grow lights come with their own built-in cooling resources. LED lights are basically made up of lots of small diodes which collectively produce light. These highly useful grow lights may be sourced and arranged so that they produce certain specific colours on the spectrum.

The main disadvantage of LED grow lights is that these are comparatively expensive, however, it should be borne in mind that over a lengthy time LEDs do tend to pay for themselves because they use measurably much less electricity. Another disadvantage of LEDs is that arrays of them may require quite a bit of space to accommodate all the necessary lights that you’d need to support your plants effectively.

The Choice For the Best Grow Lights for Your Hydroponic System

So you can see that the grow lights that you choose can be a considerable proportion of your hydroponics system’s expenditure. As far as choosing which is best for your own system, do bear in mind that there is a difference between the initial investment in buying grow lights and the cost of running them through time as part of the growing cycle of your plants. So if the lights are really cheap to run, factor in these inexpensive running costs with the initial purchase price to get a more realistic expenditure figure.

For those novices who are on a bit of a tight budget, a good choice would be CFL grow lights. They are suitable for smaller plants that need only a little light and they are comparatively cheap to buy and run.

It may be useful for you to consider using different kinds of lights for the various stages of your plant’s growth cycle, and so matching your lights to your plants more closely. MH lights and CMH lights are used for the best effect during the vegetative stages of the plant’s growth, while HP lights are better during the flowering phase.

If you are fortunate enough to have a larger budget, LED lights are a very good choice. Although LEDs are comparatively expensive when considered as a purchase investment, they will pay for themselves over time due to their excellent efficiency. LEDs also have a very wide colour spectrum, and for this reason, they will suit all the stages of your plant’s growth cycle.

You’ll really need some kind of ventilation system because of the heat that these LEDs give off (although this is not a huge amount of heat when compared with some other grow light types) and there are various options available for this. If you have a larger budget you might want to invest in something you might not have previously considered: a water chiller. Water chillers are great for long-term control of your plants’ temperature within their overall controlled environment, and having just one of these will keep your plants at their optimal good and healthy condition. Water chillers will last for ages as well.

The Component Parts of a Hydroponic Grow Light System

Hydroponic grow light systems can be said to have four main component parts, and these can be considered separately and in detail. The four component parts are the bulb, the reflector hood, the ballast, and the timer.

The Grow Light System’s Bulb.  A large number of hydroponic growers make use of High-Intensity Discharge lights (HID). Bulbs of this type produce light from an arc of electricity from two electrodes. The electrodes are contained in a mixture of gas and metal salts. The gas helps in creating the arc, and the arc evaporates the metal salts which produces a brilliant white light.

Bulbs of the metal halide (MH) variety are suitable for most plants and provide a decent, all-around light that very well represents all colours within the colour spectrum. Metal halide is a reasonable choice if you only have space for one type because of the comprehensive spectrum coverage which is produced by this quality of white light. Their lifespan is two years or less, although they become less efficient after a year or so, which means that you may well consider buying a new one at the 12 to the 16-month point.

The best bulb for the growing plants during their flowering or fruiting phase is the high-pressure sodium (HPS) bulb. These are a bit more costly, so many growers combine them with a metal halide (MH) bulb. This makes sense as the MH is a good choice during the plants’ vegetative phase in the growth cycle. It should be borne in mind, though, that HPS bulbs have a lifetime of as long as five years, which is over twice as long as their MH counterpart. Many growers find it sensible to replace them after only two years, though, as their efficiency, like the MH ones, begins to dwindle at around this time, depending on use.

The Reflector Hood. This is simply the casing that surrounds the bulb; as you would expect, the reflector hood boosts the overall efficiency of its bulb. It does so by means of reflecting light right down at many different angles so that the plants are bathed in light from a far greater number of directions. The surge of extra light in this way effectively gives the plant more light without the corresponding increase in the heat which is given off. This, in turn, means that cooling costs are reduced as well as the overall cost of electricity over time.

The Remote ballast. This consists of the power unit which powers the bulb. It works by regulating and controlling the voltage which the bulb receives; it prevents overheating and the risk of the bulb exploding. Ballasts may be bought as part of the lamp assembly itself, but this arrangement can be too heavy and hot, so a remote ballast is recommended for hydroponic systems. It should never get wet and should be protected as it is the most expensive part in any grow light system, so it is standard and best practice to keep them above the ground in the event of a leak or, worse still, a flood, which is more of a risk with a Flood and Drain system. You should buy your ballast together with your bulb (ensuring that they are compatible) as they should be of equal wattage.

The Timer. Your timer is the least expensive component of the grow light setup, although the importance of the timer cannot be overstated. Timers need to be robust and the electric variety should be grounded with a three-prong (earthing) mains plug, although manual timers are also used. In fact, manual timers tend to be more popular with hydroponic gardeners as they fail far less often than the electric type. The manual type of timer uses a pin system and some can be attached to more than one lamp at a time.

And the Best Type of Grow Light for Hydroponics is …?

The above is all very well. But how do you actually decide which type of grow light is best for your own hydroponics system?

Fluorescent grow lights have been with us for quite a long time and are comparatively cheap to run. The little heat that they emit means that they can be placed very near plants without worrying about causing damage. However, fluorescent lights have one disadvantage which means that they cannot win the top prize for the average hydroponics system grow bulb of choice, and that is that the light they emit isn’t quite strong enough to allow the light to penetrate through the outer leaves of your plants.

You could go and tick off the pros and cons for each type of grow light. But when you do that and examine all the reasons for this, there is only one outright winner….

LED Grow Lights are the Best for Hydroponics Systems!

LED grow lights are relatively new to hydroponics when compared with the other types. While they are comparatively expensive, this is compensated by several other unquestionably beneficial characteristics, all of which combine to make LED grow lights the best.

Economies of scale always kick in at some point, so the more popular LED grow lights become, the more units will be produced and so the unit costs will continue their downward movement; they’re becoming cheaper and cheaper by the month.

One piece of advice at this stage: always go for the LED grow lights which are 2.0 micromoles per watt as an absolute minimum, and don’t consider any which are lower.

At the moment the least expensive LEDs will not sustain flowering plants, so you’ll need backup when that time comes. But technology continues apace, and it’s only a matter of time before this gap is filled as costs fall further and you get stronger lights for your money.

The advantages of LED grow lights are that they are highly efficient to run, so much so that, calculated in the long term, they are among the least expensive light types to use.

LED grow lights are very easy to use and are ideal for beginners and experienced growers alike.

LED grow lights give off more light, in general, calculated per watt, than HID lights and fluorescent lights.

LED grow lights emit far less heat so the chances of your plants being burnt or harmed by their light source is very slim.

LED grow lights do not require ballast in order to work optimally, and they may easily be directly plugged into your mains electricity supply.

LED grow lights last a long time when compared with the opposition. Quite often growers have reported that the control unit gives up before the light bulbs do.

LED grow lights succeed in covering a huge colour spectrum range, and they’re also easy to adjust to cater for all phases of your plant’s growth cycle.

Of the disadvantages, they are – for the moment at least – more expensive than their counterparts. Some LED systems emit less light than certain other types of light systems. And some LEDs are – again just at the moment – not powerful enough to support plants that are at the flowering phase of their growth cycle.

See the range of LEDs we have in our online store. In particular, we recommend the Maxibright Daylight 300W Full Spectrum LED Grow Light for medium-sized hydroponic systems, while the Lumatek Zeus 1000W Xtreme PPFD CO2 LED Grow Light will be for the more ambitious grower.

But even while LED grow lights are demonstrably better than their competitors, we should also remember that technology, in the form of their manufacturers’ drive for improvements, is constantly striving to make them better and better. So we can all look forward to even greater efficiencies, lower prices and better longevity than these little wonders enjoy today!