Types of Hydroponics

The market is full of many different types of hydroponics systems, and it can be hard to pick the right one. The hydroponics system you end up buying will have a big influence on how much time and money you need to maintain your garden, which hydroponics nutrients you buy, and what plants you are able to grow.

There are two main kinds of system: active and passive. Passive types deliver nutrients via the growing medium, but active systems use a pump. An active system will cost more and take more to maintain, but may get better results. Below are examples and explanations of the most popular hydroponics types being used today.

Popular Types of Hydroponics

» The Aeroponics System: This method is probably the most high-tech type of hydroponics gardening. Aeroponics Systems use little to no growing medium. The roots hang in the air and are misted with nutrient solution. The misting is usually done every few minutes. Because the roots are exposed to the air, the roots will dry out rapidly if the misting cycles are interrupted.

A timer controls the nutrient pump much like other types of hydroponic systems, except the aeroponics system needs a short cycle timer that runs the pump for a few seconds every couple of minutes. Other types of Aeroponics systems run constantly, requiring no timer.

These systems are easily contaminated by rot-inducing anaerobic bacteria, and should only be used by experienced gardeners and researchers.

» The Deep Water Culture System: This is the simplest of all active hydroponics systems. Plants are in a basket of grow rocks, suspended over a container of aerated nutrient solution. An air pump supplies air to the air stone that bubbles the nutrient solution and supplies oxygen to the roots of the plants. 

Water culture is the system of choice for growing leaf lettuce, which are fast growing water loving plants, making them an ideal choice for this type of hydroponics system. Very few plants other than lettuce will do well in this type of system, although it can work well for the vegetative stage of flowering plants. This type of hydroponics system is great for the classroom and is popular with teachers.

A very inexpensive system can be made out of an old aquarium or other water tight container. The biggest drawback of this kind of system is that it doesn't work well with large plants or with long-term plants.  

» The Drip System: This method is probably the most widely used type of hydroponic system in the world. Operation is simple; a timer controls a submersed pump. The timer turns the pump on and nutrient solution is dripped onto the base of each plant by a small drip line.

In a Recirculating Drip System the runoff is collected back in the reservoir for re-use. The Water-to-Waste System does not collect the runoff. The advantage of Water-to-Waste is that the nutrient solution in the reservoir has never passed through the system, so it is unchanged. In a Recirculating System, the nutrient solution can fluctuate in both nutrient concentration levels and pH levels.

We recommend a soilless mix for Water-to-Waste systems, because soilless mixes retain more water. This way, the pump kicks on less often, so you use less nutrient solution. With quality nutrients and a good soilless mix, a Water-to-Waste Drip System can be one of the best ways of gardening with lights. 

»  The Ebb and Flow System: Ebb and Flow works by temporarily flooding the grow tray with nutrient solution and then draining the solution back into the reservoir. This action is normally done with a submerged pump that is connected to a timer. When the timer turns the pump on nutrient solution is pumped into the grow tray. When the timer shuts the pump off the nutrient solution flows back into the reservoir. Depending on plant requirements, the tray can be flooded once, or several times, each day.

The main disadvantage of this type of system is that with some loose types of growing medium (Growrocks, Perlite, etc.), there is a vulnerability to power outages as well as pump and timer failures. The roots can dry out quickly when the watering cycles are interrupted. This problem can be relieved somewhat by using growing media that retains more water (Rockwool, coconut fiber or a good soilless mix).

This is the system we often recommend for first-time hydroponics gardeners. It is simple, reliable, and easy to set up.

» The N.F.T. System: N.F.T. systems have a constant flow of nutrient solution so no timer is required for the submersible pump. The nutrient solution is pumped into the growing tray (usually a tube) and flows over the roots of the plants, and then drains back into the reservoir.

Normally the plant is supported in a small plastic basket full of grow rocks, with the roots dangling into the nutrient solution. N.F.T. systems are very susceptible to power outages and pump failures. The roots dry out very rapidly when the flow of nutrient solution is interrupted.

There is usually no growing medium used other than air, which saves the expense of replacing the growing medium after every crop. Normally the plant is supported in a small plastic basket with the roots dangling into the nutrient solution.   

Hydroponics - The Future

"Gas and food prices are increasing, persuading people to take matters into their own hands." The National Gardening Association expects 43 million American households to grow their own fruits, vegetables, herbs and berries this year." That's up 19 percent over last year, according to a household survey the group conducted in January (Sutter, 2009).

People are enjoying the satisfaction of growing their own food, the enhanced flavor and the saved money they benefit by doing it themselves.

"Environmentally friendly" has become a mantra amongst those wanting to preserve our planet and stop the exploitation of the very land we depend upon. With this, many are utilizing the benefits of composting and growing their own food. This trend to protect and sustain our fragile planet is one that will continue to grow in the future. The movement towards a more health conscious society is on the rise, providing an unmeasured opportunity for hydroponics and organic gardening.  

Not only are individuals growing their own food, but restaurants and even grocery stores have implemented their own gardening centers to offer fresh, local produce to their customers. They have heard the voice of the people wanting uncontaminated foods grown in their own community.