I'm often inspired by @isdarmady and his hydroponics posts so I thought I'd share an overview of our setup. Some of you may have seen aspects of its development in earlier posts but this is the nearly mature version. All I need to do now is to build a greenhouse over it and I'm done (folks who know me will laugh at that!).
Our system was based on fish as the primary source of plant nutrients but we had several die-offs in extremely cold weather. We never ate the fish either, so that was a big part of the payoff from an aquaponic system that we didn't benefit from (plus there was the expense of food for the fish).
So now, for the most part, it is what is called a 'bioponics' system. I make all of the liquid fertilizers myself and they get shared between the 'ponics and the perennial garden at the front of the house. I do buy a little commercial fertilizer every few months That is a just pack of Thrive soluble fertilizer which helps me to balance the micronutrients. I haven't reached a suitable skill level in fertilizer making to guarantee the amounts of these in the final brews. I know most are there, just not how much.
Our system takes up most of our tiny backyard.
Flood and Drain
Mixed media and a Bell Siphon in a flood and drain bed.
I've built it all in three separate systems. The main system consists of 6 Flood and Drain beds which contain a mix of scoria and clay balls. The scoria is in there to weigh down the clay balls otherwise when the bed fills, the clay balls float!
'Flood and Drain' means that the bed fills to a certain height with water and then drains almost completely via a simple device called a Bell Siphon. Using this method, air is pulled down into the media and oxygenates the plant roots. It also means that I can keep worms in the beds to eat a lot of the broken or rotting plant material and that means that I don't need to worry about filtration as much (cleaning filters is yucky!).
The water flows through these in cycles of flood and drain and flows back to the sump tanks that are located below the beds and is where the pump is located.
In Summer, the pump runs for 15 minutes of every hour throughout the day and early evening. that kicks off several flood and drain cycles each run and lets water drain back into the sump when it is not running. I do this for two reasons: first, it saves power and second, I have only shallow tubs for the sumps so allowing water to drain back helps fill them more before pumping sarts, reducing the risk of the water level in tubs being too low to pump.
In Winter, I run the pumps continuously during daylight hours except for two half hour breaks during that time to help replenish the sump. It's necessary to cycle the water more often in Winter because when the water is cold, it carries less oxygen which doesn't reach the plant roots.
The constant height bed with grow pipes on the fence.
The second system that we have is a combo system. It is made of two parts of an IBC (Intermediate Bulk Container) which is one of those big white plastic cubes that companies ship fluids in.
The first part of this system makes use of a little fence height that we have behind the tubs. Water pumps up from the system's sump and flows through pipes set horizontally along the fence. Holes have been cut into the pipe to allow net pots and plants to sit there. The water from this part flows to the next part, the Constant Height bed.
The second part of this system is a Constant Height Media Bed. Like the other media beds, this is filed with a mix of clay balls and scoria but unlike the Flood and Drain beds, water is always flowing through it at a set height.
The water flows from that part to a Floating Raft Bed. Floating rafts are large sheets of construction styrofoam with holes cut in them. Into these holes go net pots which contain a little media and a plant. The roots grow down into the water and feed the plant. I made this bed in this style because I couldn't afford to fill it with media. Whe I can afford that, I'll convert it to another Constant Height Media Bed.
From there the water flows back into the sump which sits below the beds and is where the pump is located.
Floating raft bed.
The separate Kratky system.
We also are running a small Kratky hydroponics system. This is an experiment which is working well. The Kratky system uses tubs of nutrient solution down into which plant roots grow. The tubs have a lid and the plant is placed in a net cup into a hole in that. The roots grow into the nutrient solution and as that solution lowers, air is drawn in to fill the void, oxygenating the plant roots.
What do we grow?
We grow all of our green, leafy vegetables through these systems with great success. In the colder weather, all of our Brassicas are grown here where they are off of the ground and (when netted) safe from the appetites of most bugs. I've started experimenting with growing Alliums in the Flood and Drain beds and have had great success growing Garlic, Shallots, Spring Onions and Bunching Onions.
In Summer, Tomatoes and Capsicum and Lettuce get planted in the Flood and Drain Beds and thrive for an extended season of growth. In the warm weather, one bed is always dedicated to our favourite green vegetable Kang Kong. Last year we experimented with growing melons in one of the beds with great success. this year we will try a few more in strategic locations to shade the rest of the back yard with their leaves.
All up, we grow about 80% of our vegetable needs through bioponics, plus there are a couple of beds dedicated to growing greens for the Chooks and Quails. Those tubs contain things like Azolla, Water Parsley and Fish Mint. These are all things that grow lushly in water based systems plus they have the benefit of soaking up extra nutrients in the system.
We have so many methods incorporated into the overall system for a couple of reasons. First, as you may know from reading earlier posts, I'm a Maker, I love to tinker and build. I've built the system up over 5 years and tested it well at every stage. The second reason is cost. Some parts such as pumps and tubs, plus the wood for the frames that support them cost heaps. I try to trade, swap, reuse and recycle where I can but sometimes, I've got to save for a while to pay with $$$ and not everyone takes HBD 😁