Where Lies The Real Magic In An Aquaponics System?
Aquaponics can seem like magic when you first hear about it. Likely when you first heard about it you heard it defined as the integration of aquaculture, or the raising of fish in a closed environment, and hydroponics, the raising of plants in a soil-less medium. And that definition permeates the industry because it’s an easy way for people to get the basics of whats happening in an aquaponics system and it shows people where the word originated from. It takes the aqua of aquaculture and combines it with the ponics of hydroponics.
For most, that’s all they’ll ever care to know about aquaponics and that definition is enough for them to comprehend what is happening and be conversational on the topic. But aquaponics is about growing more than just fish and plants. See in aquaponics the fish produce waste from their breathing and their bodies in the form of ammonia. Ammonia is toxic to both fish and plants. So without the crucial third component of aquaponics, the thing we really should think of ourselves as farming, the awesome symbiosis of the fish and the plants wouldn’t occur.
The real secret in aquaponics lies in how that ammonia waste gets transformed into something useful for our plants. The plants in the aquaponics system are feeding of Nitrate, a form of nitrogen. To get from ammonia to nitrate is a two step process. Anyone familiar with their nitrogen cycle will know that first ammonia gets converted into nitrite. Nitrite is still toxic to both fish and plants so we need one more conversion to get from nitrite to nitrate the form of nitrogen that our plants love so much.
What is driving these conversions? That’s the real secret driver that makes aquaponics such an incredible and sustainable method of agriculture. That’s really what you need to consider yourself farming cause without these little guys you’d just have stinky water that was no help to your plants and your plants would then be no help in cleaning the water for your fish. That’s why we created the Aquaponics Trifecta PDF (115 downloads) to make sure that everyone is aware of the role of microbes in their systems
It’s All About The Microbes Baby
In aquaponics, we have beneficial microorganisms that assist with the conversion of our ammonia into our nitrate plant food. These beneficial bacteria are naturally occurring all around us in our environment and so we don’t need to do anything to make the magic happen, but we do need to be conscious of the role these bacteria have in our system and ensure we are creating an environment in which they can thrive.
If you are familiar with probiotics then you understand the concept between beneficial bacteria and harmful bacteria. Our aquaponics systems thrive on aerobic or oxygen loving bacteria. Specifically, we are interested in helping to cultivate Nitrosomonas and Nitrobacter bacteria. The Nitrosomonas eat the ammonia bacteria and produce nitrite as a waste product. The Nitrobacter then eat those nitrites and produce nitrate as a waste product. From there it’s the plants turn to get in on the action as they take up nitrate via their roots removing it from the water and filtering the water as a result. With the nitrate removed we can send the water back to the fish for them to repopulate with ammonia.
As you can see, our beneficial bacteria play a key role in the success of every aquaponics system. That’s why the real secret to a successful aquaponics system is to focus on creating an environment for your microbes to thrive. A thriving microbe population will ensure your fish waste is processed efficiently and your plants have the nitrate they need to grow efficiently.
Three Keys To Growing A Healthy Microbe Population
1. Oxygen Oxygen Oxygen
As we identified in the section above, our teams of bacteria are aerobic bacteria meaning that they need oxygen to survive and reproduce. This means we want to make sure that our system water is well oxygenated and also make sure that we don’t have any areas in our system that can turn anaerobic on us (not have enough oxygen). That is why it is always best to aerate both your aquaculture tanks and your hydroponic grow beds. You also want to turn over your fish tank at least once an hour, meaning water should be flowing constantly through your system so it does not spend too much time in any one area. If you have an area of your system that doesn’t get aerated or turned over regularly, like potentially a sump tank, consider adding an aerator with an air stone to it to keep it from becoming an anaerobic dead zone in your system.
2. BSA or Biological Surface Area
Our bacteria need a place to live and to reproduce. Specifically, they need a lot of Biological Surface Area (BSA) to thrive. WHat is BSA is basically anything that has a lot of tiny holes in it. In aquaponics, the media we use in our bio filters and or media beds is where we are going to get the majority of our biological surface area. The media used in a media bed is a great place to illustrate this concept. Whether you use expanded shale, clay or some other aggregate your little pieces of media look solid from afar but if you look up close you’ll see they are very porous. Each little rock has hundreds of little holes where your bacteria live. Think of each little rock like an apartment building in a big city. From the outside, it looks like one big building but when you see inside of it you see that it has dozens of separate rooms and people living in each separate room. The little holes in our media are like the apartment units in an apartment building. The more porosity a media has, the more bacteria life it can house and support. In order for your aquaponics systems to thrive you need a thriving population of beneficial bacteria and for that, you need enough BSA to support that thriving population. When choosing media for your beds or filters, make sure it has a high BSA. And if in doubt, stick to the tried and true medias for hydroponics and aquaculture or ask an expert. You can always drop us a line in the chat box for any help with choosing your media.
3. Water Temp
Temperature is key for the reproduction of our nitrifying bacteria. The temperature for optimum growth of nitrifying bacteria is between 77-86° F (25-30° C). The growth rate is decreased by 50% at 64° F (18° C). So depending on your fish variety you may not be keeping your system at the temperature necessary for optimal growth. That is ok so long as you have enough BSA to compensate for slightly decreased growth rates but you should aim to keep your system above 65 degrees to maintain efficiencies. By that same token too hot is no good either, try to keep your system below 90 degrees even in the heat of the summer. You don’t want to accidentally nuke all your little workers leaving your system to fall out of equilibrium.
Happy Microbes Happy Aquaponics
While there is admittedly a lot more that goes into an overall strong aquaponics system, the microbes are the foundation for the success. Without a healthy population of nitrifying bacteria, all the integrated pest management or optimized lighting or regimented nutrient scheduling won’t help you. You need that nitrification process in place in order for the magic of aquaponics to happen. So follow the three keys to maintaining a healthy microbe population and you’ll be growing to your fullest potential from day one.