Ebb And Flow
Ebb and flow to me is the bread and butter system of the hydroponic world. This system is super easy to set up and in most cases will be the cheapest hydroponic system anyone could build for their plants.
Ebb and flow, also known as flood and drain, consists of a reservoir containing your water and nutrients transported via a water pump to a flood tray and then back to the reservoir. It is important to keep the holes at the lowest point in the tray because most of the time you will be drilling the holes yourself.
Make sure each hole for the intake and overflow include a water tight fitting to avoid leaks. Your plants in whatever growing medium you choose will rest in the flood tray. Based on what growing medium you choose will help you find a good watering schedule. One of the biggest factors being how absorbent the medium is because you want to avoid letting your plants sit in nutrient solution.
The next note would be to make sure that the tray you buy does not have a flat bottom. Trays etched in channels help with getting nutrients back to the overflow. Think of it as if you are making lemonade with a powder mix. When you put too much in the excess powder will sit on the bottom. This is the exact problem you are trying to avoid when it comes to getting your plants nutrients.
Now you may be asking how does this help my plants? Well to explain that i would like to bring your mind to a more natural setting. Around rivers and streams you may notice that plants roots are more exposed and make more contact with air than one you would find in a field. This is because the plant will structure it’s roots based on the environment that it is exposed to.
The plant is accustomed to receiving water and nutrients during high times in the river and then gets revitalized by fresh air once the water levels drop. These series of events lead to an increase in metabolic rate in plants and allows them to grow strong and healthy in comparison to hand watering your plants.
Now you’re asking how do I know when to flood the trays? Well that’s where things get a little more complicated. This is because as your plants grow you are going to change watering schedules cuz obviously bigger plants need more resources.
So this area is a bit trial and error and requires you to pay attention to how your plants are responding. I recommend adding just water or half strength nutrients mixtures into the reservoir often.
Checking the water lever frequently as well as the Ph of the solution because plants need more water than nutrients. Meaning that the amount of nutrients you put in isn’t all being used but the water is. This will make the solution in the reservoir very concentrated over time and can do some real damage to your grow operation.