A Straightforward Guide to Run To Waste Hydroponic System

Run to waste

When it comes to hydroponics, there are two systems you can use. These two options are recycling systems and run to waste hydroponic system. Each design offers a fantastic world of benefits and advantages, but they also present some drawbacks.


In today’s article, we’ll focus on what a run to waste system is. We will cover everything from how it works to the benefits it provides.



How Do Run To Waste Hydroponic System Work?

Traditional Agriculture Top Drip Irrigation, Run to waste, Source

If you hear run to waste hydroponic systems, you should think of systems where the nutrients are not recycled. Unlike recycling systems, this setup does not reuse nutrients and water over and over again. However, there’s a reason for this type of system: its many benefits.


Run to waste systems are very similar to soil systems. They both have a high fluid retention rate, and that retention is what keeps the nutrients in the plants. Whereas recycling systems move the water and reuse it, run to waste allows the grow trays to retain enough moisture for the plants to absorb the nutrients for longer.


In other words, in a run to waste hydroponic system, the excess nutrients are disposed of. The extra nutrients are known as run-off. Calculating the necessary nutrients and controlling the run-off amount allows you to plan better. By doing so, you can reduce the risk of under-dosing or overdose.


Usually, run to waste hydroponic systems’ users calculate and plan their feeding so that the run-off percentage stays within 10 to 20 percent. This calculation produces one of the systems’ most significant drawbacks: disposing of the run-off.


Additionally, run-to-waste hydroponic systems do not require the constant feedings that recycling systems need. That’s one reason many experts prefer this type of hydroponics.



Advantages and Disadvantages of Run To Waste Hydroponic System

Run to waste system
Run to waste hydroponic system, Source


There are many advantages to run to waste hydroponic systems, from no nutrient exhaustion to less maintenance. However, run-to-waste hydroponics do present certain drawbacks that are absent in recycling systems.



Here are the main advantages of having a run to waste hydroponic system:


  • Nutrient exhaustion: One of the main advantages of a run to waste hydroponic system is that it exponentially reduces nutrient exhaustion. Recycling systems reuse nutrients, meaning that each time the plant reuses the nutrient, it has less value. It means that your plants are not getting the same amount of nutrients every time. Run-to-waste systems work differently. They do not reuse nutrients, and by using new nutrients every time, they can provide the amount needed. Every time you feed your plants with this system, they get new and fresh nutrients, and you can control the amount.
  • Better pH stability: One of the main drawbacks of recycling systems is pH stability. As the system reuses the nutrients and water, the pH gets harder to control, which can harm your plants. On the other hand, run to waste systems provide a more stable pH with each feeding.
  • EC stability: The EC percentage of your hydroponic system results from the number of salts inside the system. All hydroponic systems require a stable EC percentage, or you risk overdosing the plants. However, recycling systems are more prone to have an unstable EC. Run to waste, on the other hand, offers more stability in terms of salts and nutrients.
  • Healthier environment: By not reusing the nutrients repeatedly, you also help your hydroponic system be a healthier environment for plants to grow. There are fewer bacteria, pathogens, fungus, and other factors that could harm your system. Additionally, nutrients will not build up sodium chloride as quickly and constantly as recycling systems.
  • Less maintenance: If you choose a run-to-waste system, you won’t have to spend much time controlling the pH or the EC levels. Using new nutrients and water reduces the need to be extra careful with your system.
  • Insulation: Because you are using fresh water with each feeding, you provide the roots with more insulation against heat. The new water will help regulate the plants’ temperature, which is one step to keeping them healthy.
  • Retention: The moisture retention in the system will last for over a day, which will help you reduce the number of feedings your plants need. This is a safety benefit if any of the pumps or the pump timer fails. Your plants will retain nutrients even if not fed for a couple of days.



Run to waste hydroponic system may sound like the superior option. Still, they do present some drawbacks compared to the recycling system.


  • Salt buildup: The type of feeding used by run-to-waste systems is known as intermediate feeding. It can lead to salt building up at the root zone of the hydroponic system. Not only is that a severe problem for the integrity of the entire system, but it can also lead to dripper blockage if not dealt with as soon as possible. If you want to minimize this risk, we recommend flushing out the water now and then.
  • Controlling the rooting zone: One main drawback of run-to-waste systems is the difficulty of maintaining the EC levels in the rooting area. Using freshwater reduces the risk of EC instability, but only on the surface. It gets difficult to control the levels underneath.
  • Waterlogging: You’ll need to pay extra attention to the watering process, as too much water can lead to waterlogging. If you give too much water to your plants, you’ll be wasting nutrients and producing a disease-friendly environment.
  • Nutrients channeled downward: Because root density tends to be lower, the system will channel the water downward instead of spreading around. If the water moves downward, it becomes more difficult to control your plants’ nutrient levels.
  • Groundwater contamination: Another major disadvantage of this type of hydroponic system is that it can lead to groundwater contamination. That’s the reason why authorities are outlawing it for commercial purposes. If you are going to use a run to waste hydroponic system, find a way to dispose of the run-offs without damaging the environment.



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A Run to waste hydroponic system is the best option for larger plants with high uptake requirements. They offer more EC and pH stability, no nutrient exhaustion, better insulation, and they are easier to manage and control. However, be wary of the drawbacks they present, like groundwater contamination and salt buildup.


Picture of Kate Beverage

Kate Beverage

I'm Kate, I worked in the DIY/home improvement field in Australia for almost six years. During that time, I cultivated an interest in indoor and outdoor living, with a particular interest in gardening and landscaping. I am passionate about living surrounded by nature and greenery, eating fresh fruit and vegetables, and minimizing my impact on the environment.