Between Hydro Crops: What to Do and What to Reuse
When you’re between crops in the indoor garden, it’s a good time to think about cleaning your system and sorting out what to keep and what to throw away. Here’s a basic guide to help you.
Maintenance between crops and on a routine basis is a must for a healthy and thriving hydroponic growing system. A few steps taken on roughly a monthly basis is all that is required, and the good news is almost every aspect of your system, if taken care of, can be reused time and again.
Hydroponic components can be costly, but fortunately, they do not have to be purchased on a continual basis. And regardless of the type of system you have, a thorough cleaning of all of the components will keep your plants productive and happy.
Cleaning a Hydroponic System
Cleaning your system while you have an active, viable and potentially harvestable crop should only be done if you see a build-up of algae and the plants are not showing any signs of stress. For these times, hydrogen peroxide can be used without harming your plants so long as the proper ratio is used. Use 0.1 oz. of hydrogen peroxide per gallon of water in your reservoir. This mix can be run through the system for 24 hours, drained and then refilled with clean water.
For cleaning your system between crops, bleach is an effective sanitizer. Add 1 tbsp. of bleach to your reservoir and run the pump for half an hour. This will kill bacteria and spores that may be lingering in the crevices of your tubing and tanks. After the bleach has been cycled through for enough time, drain all of the water, nutrients and all, out of your system.
This water does not have to go to waste! It can be used to water your lawns or gardens. Wipe clean any residue or grime in the reservoir, pipes and pump. The system is now ready to be refilled with clean water, preferably rainwater, and your nutrient solution of choice.
What Can Be Reused in a Grow Room in the Next Growth Cycle?
Though many parts of your system will eventually have to be replaced, the good news is most can be used multiple times in succession. Your hydroponic infrastructure should last you several years before you have to replace or upgrade it. This includes your reservoirs, pumps, irrigation lines and light ballasts.
The useful lives of the more disposable components depend largely on the type and quality you have chosen. If your pump has a removable or sponge type filter, this can and should be removed for cleaning. A mild bleach solution as prescribed by the manufacturer should suffice as a bactericide and algaecide, but it should also be wrung out by hand with hot water.
Media such as gravel or clay pellets can be reused time and again, so long as they are cleaned with the rest of the system. This goes for most mesh pots and other containers. If they are properly sanitized between crops and uses, there is no reason to replace them often.
What Should Be Replaced?
A lot of the hydroponic supplies that can be used multiple times have a productive lifetime that will eventually expire. Just like us, no component will work in perpetuity. There is some supplies that should not be reused under any circumstance.
Wear and tear parts that should be replaced often or at the very least as needed include your pump’s filter, bulbs for your grow lights and irrigation lines or tubing. Over time, your filter will get worn down, corroded and blocked.
Follow the manufacturer’s guidelines on replacement to ensure you are not trying to save a few bucks on parts only to have your crops suffer for it. Lights should be replaced at a minimum of once per year, except LEDs, which last longer. Even though a bulb may not be blown out, every time it is turned on, it is emitting a little less energy than the time it was ignited before.
This weakened output is not often perceivable to the human eye, but the effects can be seen in less vigorous plants, fewer or smaller fruits, or at least slower growth. Your tubing should be inspected for cracks, kinks and discoloration. Lines should be replaced as needed, but do not expect them to last more than a few years at best.
Many types of grow media are difficult to be reused or should not be reused multiple times. These include fiber media such as rockwool and coir. Over time, these materials collect foreign debris circulating in your system and compromise the hygiene of the hydroponic system.
Perlite is another type of media that should be replaced often. The smaller the materials or particles of your media is, the greater the surface area it has to collect debris, bacteria and algae. Inspect your media regularly.
What to do After a Thorough Cleaning in the Grow Room
Once you are satisfied your system has been effectively cleaned, you can begin preparations for the next crop. Start by refilling the reservoir with clean water, then add the media. Next, the pots or floating receptacles can be installed. Plants or seeds should be placed in the media after the containers are set. Finally, add your nutrient solution to the reservoir. Take measure of your system often after you have cleaned it. Hopefully your maintenance practices help your system achieve a desirable pH and EC.
Many components of your hydroponic garden will give you years of dedicated service, so long as a little care is given.
Written by Chris Bond | Certified Permaculture Designer, Nursery Technician, Nursery Professional
Chris Bond’s research interests are with sustainable agriculture, biological pest control, and alternative growing methods. He is a certified permaculture designer and certified nursery technician in Ohio and a certified nursery professional in New York, where he got his start in growing.