I had a look at an Aquaponics and though I quite liked the system there where some things I didn't like about it such as the energy consumption of the pumps and that amount of fish in a small amount of water can cause problems with all the fish dyeing.
edit 26/7/12 Just a note on growing root vegetables. A number of readers have pointed out that some people have successfully grown root crops in both a hydroponic and aquaponic systems. I have also spoken to "experts" who have told me no way, there are problems with crops going rotten. http://www.instructables.com/id/Hydroponic-Food-Factory/step17/Hydroponic-potatoes/ give a short description on how to grow potatoes in a hydroponic system.
I'm not able to grow a traditional garden, as we have extremely poor soil, water restrictions, low rain fall, and extreme weather events such as week long heat waves of 45C or 113F which will kill any veggie within hours.
I started this project about a year ago and at the time it was an experiment to try an address the above issues, I had never heard of vermiponics, and there is still not a great deal of info about it. It wasn't until a few weeks ago I found that it had a name and there are some similar systems out there. Stupidly I didn't take a lot of photos and it is now July and the middle of winter so the garden doesn't look that good at the moment. I will up date photos every month for the next year or so.
Step 1: How it works
The bottom tanks are joined together with poly pipe and a solar pump, pumps water to the top storage tank. The top storage tank has a siphon inside it and that trips off around every half hour in full sun, which waters the plants. The plants are grown in soil and taste fantastic (no sad watery acid hydroponic tomatoes here)
The soil in this area is very poor and aqua-phobic ( will not absorb water) so I use a mixture of soil, animal manure, lawn clippings, leaves, food scraps,wood ash and a box of worms to get it started. The worms have gone mad and turned the soil in to rich dark loam and the plants have thrived.
Below the soil is several layers of shade cloth to keep the soil out of the layer of gravel which is at the bottom of the top tank and to provide drainage and a home for microbes. The water then drains into the bottom tank and the process starts again.
I had a problem with mosquitoes in the bottom tanks when first set up, a couple of gold fish in each tank soon fixed that.
Another problem when first set up before the worms became established was the soils poor nutrient level as the plants were not growing very well, some organic liquid fertilizer helped in those first few months
As the worms started working the water became so full of nutrients that it became possible to grow leafy greens in a gravel bed.
Here is my first crop of lettuces grown in gravel.
Step 2: Stuff you will need
- IBC containers can be purchased cheaply and some places give them away, just check the condition, (holes or UV damage) and contents as they may have been used to transport some nasty chemicals or herbicides which wouldn't be good for you health.
- Poly pipe and fittings are cheap as chips, and can be purchased almost anywhere
- Irrigation grommets are a little harder to find, try a big irrigation suppler
- Solar panel and pump ebay is great for this sort of stuff but make sure that it has a good head height at least 2 meters
- 60 to 100 litter plastic drum
- Tech screws
- Compost, soil, manure, worms
- Shade cloth or similar material to keep dirt out of the gravel, but allows water to pass through
- Tools cordless drill, jig saw, hole saw etc
Step 3: IBC modifcation
Next tech screw the 2 bars you removed from the top and fit half way up the cage, and drop in the top, upside down. Tech screw this into place and drill some drainage holes in bottom. Repeat to as many IBC you think you will need.
Connect the tanks together with the grommet fittings and poly pipe (you will need the right size hole saw for this)
Step 4: Making the worms welcome
Step 5: Setting up the irrigation
The hard part is setting up the syphon system. These little pumps don't have the flow to run all the sprinklers at once, and that would not be a good thing as the plants would drown. A siphon gives the plant a drink about every half hour for 2 or 3 minutes in full sun, less on cloudy days and nothing at night or rainy days. I was hoping to find a few good GIFs to explain, sadly that's the best I could find. The siphon is commonly used in aquapnoic systems and there is loads of info on youtube and other websites. The GIF is a bell siphon and is basicly the same principal for all siphons, I have used the 2 loop siphons shown in the diagram, the internal siphon inside the top tank, and the normal loop on the gravel grow bed. They can be tricky to set up but once working they require no maintenance and are very reliable. Here are some pointers.
- Use tube that keeps its shape (does not crush) as even a small amount of flatness in the tube upsets the siphon.
- Use clear tube so you can see the water flow and how it works.
- The path of the tube needs to be circular as shown
- It s important for the siphon to get a big gulp of air at the end of its cycle as this stops the flow of water
- Attach the end of the siphon to the side of the grow bed not the bottom as shown in the diagram as it works better on the side.
- The siphon requires a high flow of water to get started and to stop, so if you plan on having sprinklers attached you will have to have a bleed off to keep the flow rate up. This can also regulate the amount of water the garden beds get. It also helps to get the tank as high as possible.
- It will take a few tries to get it right
- On the internal loop siphon that I made is circular ( like the loop siphon) and tied some elastic to the top of the loop to give the tube a bit of "spring" this makes the siphon stop more reliably as it jumps up a little when it gulps some air.
Step 6: More on irrigation
Here is a couple of photos of the siphons, the one inside the top tank is hard to photograph but the elastic is shown at the top of the tube. The "sprinklers" are just 2.5mm holes drilled in the tube which are easy to keep clean and very cheap.
To link the tanks together I used these rubber grommets that I got from an irrigation supplier, the work well and don't, leak just drill a hole and push in the grommet and then the fitting.
And finally some quick cad drawings of the siphon system with the bleed valve.
I found that it certainly was worth the effort and we have had a huge amount of food from this small garden. We were able to grow capsicum (bell peppers), basil, egg plant, tomatoes, zucchini lettuces, melons, beetroot, spring onions, cucumbers, in amounts that we gave much of the veggies away.
The last photo is of the cover that was put on to stop the frosts, (thanks piks) in spring and summer it had no cover and the small amount of rain helped kept the tanks topped up. The cover has small holes in it, again so when it rains it helps fill up the tanks.
Step 7: July (Winter)
I will pull out some of the older plants and get some new crops in the ground when the weather settles down.
Step 8: August (winter)
Step 9: September (spring kind of)
Step 10: October (spring)
I have also thrown some seeds in the gravel bed which have all germinate and has the bonus of the birds not wanting to dig up the new plants, I guess they don't like gravel.
The Fish are becoming more active as the weather warms up and are keeping the insects down.
The plants that are in the soil grow beds are doing well, but I have always had problems growing broccoli as they attract all manner of pests and this year is no exception, they were attacked by pest unknown, I suspect rat, bat, possum or a starving hobo.
Step 11: November (spring)
in the last 3 week or so the zucchini s have really started producing and we are having them ever second night or so and already started giving excess away. I had some success with potatoes but some of the plants were attacked by slaters which was a disappointment, I need to be a bit more careful with the mulch introducing pests
Step 12: December January Summer
In January we had a heat wave with several days above 40 degrees C and high winds so some plants didn't survive. I should really put some shade cloth over the garden. Egg plants and zucchinis are doing well but most other plants are struggling with the heat even the water melon are not happy.
The fish are thriving and have increase dramaticly in size, some have even become tame and you can now hand feed them. The warm weather has also increased their appetite they seem to be always hungry.