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6 Ways to Prevent Bacteria (Slimy Roots) in Hydroponics

Hydroponics is a great way to get a good crop in an urban environment. However, this technology has both strengths and weaknesses. One of the weaknesses is the occurrence of bacteria on the roots.

To prevent bacteria in hydroponics, keep the solution temperature no higher than 72°F (22°C). Make sure that the solution is well oxygenated. Also, change the water at least twice a month. Be sure to run fresh water through a UV sterilizer before pouring it into the system.

These are basic recommendations to avoid slimy roots. We will cover all of these tips and a few others in detail in this article.

bacteria in hydroponics

Slimy Roots

Maintain the right temperature

Usually, the bacteria are in the water all the time, but they become most active when the temperature rises. Most bacteria need about 72-74 degrees to start multiplying.

This means that you have to keep the water in the hydroponics below 72 degrees. However, the plants also need a warm environment to thrive, so make sure the temperature does not drop below 59 degrees.

The cause of overheated water in hydroponics is often the pump. It releases heat into the water during operation, and you can only solve this problem by cooling the water.

If your hydroponic system is not equipped with a thermometer be sure to install one. Constantly monitor the water temperature and if it rises above the recommended level, cool it down.

The most practical solution is to install an air cooler near the hydroponics system. You can also set your air conditioner to the appropriate temperature in the hydroponic room.

Read also: What is the best hydroponics for indoor use?

Give extra oxygen

The next cause of slimy roots in hydroponics can be a lack of oxygen in the solution. Oxygen in hydroponics is needed not only for the plant to grow better but also for the oxidation of bacteria, resulting in the death of bacteria.

Some hydroponic systems are not equipped with oxygen pumps at all and according to the idea of the developers the oxygen should enter the water due to water movement caused by the water pump. However, in practice, this does not work and the water is oxygenated insufficiently.

If you encounter slimy roots and your system does not have an air pump with air stones then install them. Choose a powerful air pump with large air stones that produce the smallest possible bubbles.

On the other hand, if you have an air pump in your hydroponics but the bacteria continue to bother you, install additional oxygenation.

Change the water regularly

Fresh water is the key to a bacteria-free system. On average, hydroponics needs a water change every two weeks. For larger systems, it may be once every 20 days.

The best water for hydroponics is distilled water. If you use this exact water, the chance of slimy roots is minimal. However, distilled water is expensive and it can lead to excessive costs especially if you have a large system.

You can also use normal tap water after purifying it. The fact is that bacteria are present in tap water even after it has been treated with chlorine. So you need to treat it with ultraviolet.

Just buy and install a UV sterilizer in your plumbing. Then by running water through it, fill the tank. Water sterilized in this way will be as good as distilled water.

Also, be sure to measure the pH of the water and adjust it to the requirements of your plants. The fact is that at an incorrect pH, bacteria can multiply faster than usual.

Keep hydroponics clean

Be sure to clean your hydroponic system along with the water changes. Bacteria usually attach to roots or organic debris that accumulate in the tank.

In a clean hydroponic system, the bacteria will have nothing to cling to and you will end up with healthy plants.

Disassemble all the parts of the system and rinse them under running water. Use a brush to clean even the smallest parts.

Then reassemble the system and fill it with water, but do not put the plants in. Add hydrogen peroxide to the water. For each gallon of water, add 10 milliliters of hydrogen peroxide.

Turn on the hydroponics and let it run for about 30 minutes. Next, drain the water and pour in the nutrient solution. You can now put the plants in place.

Make sure that your water pump has a filter. If not, install one if possible. Clean the filter every 5-7 days.

Avoid root clogging

root clogging

Root clogging

One of the problems of hydroponics is root clogging. Because the roots do not encounter any resistance they begin to grow very intensively and clog the tank in which they are located. This leads to poor water movement and consequently to the rapid growth of bacteria.

Moreover, it increases the load on the pump. As a result, the pump overheats and increases the temperature of the water. As you already know warm water is the ideal environment for bacterial growth.

To avoid this check the roots of your plants constantly. Cut them off as soon as they start to bind and clog the water channels.

But try not to cut more than 25% of the root system for each plant. Cut them back starting at the bottom. Always use a sterile pruning tool.

Make sure the reservoir is completely dark

The last thing you need to take care of is that the hydroponic system must be completely dark inside. If the walls of the tank let in sunlight, or light in any other way penetrates inside the system, algae will grow there.

Algae itself is not good for plant growth. Algae also slow down water movement and are a breeding ground for bacteria.

To avoid clogging your hydroponics system with algae, be sure to check all elements for light penetration. If necessary, paint the tank black. Also, seal all places where light enters the system.

Bottom line

All in all, any of the tips outlined here can greatly reduce the possibility of bacterial growth in hydroponics. At the same time, if you follow all the recommendations, you will almost certainly avoid slimy roots and get a bountiful harvest.