The key with the compost tea is minimising the amount of compost you need to feed the plants. A fancy name for soil samples added to the midden from around the property is 'Indigenous micro-organisms, or 'IMOs'. Though I haven't tried it yet, it seems to be a very efficient way of spreading desirable micro-organisms to the plant production areas. If the soil is kept moist, and the rest of the soil food web is established by nature, you should only need to use the Permafert slurry once in a given location (also remembering that the majority of the biochar matrix will last for 100s to 1000s of years, depending on the characteristics of the biochar produced eg. high temperature and high silica content). I just have to find a cheap aerator, so possibly a second hand aquarium pump/aerator will do. The 20l buckets should be easy to get from virtually any restaurant in the industrialised world. A laundry bag with a zipper could be used for the 'tea bag' and the structure holding the tea bag can be made from PVC pipe and joiners then placed in a 20l barrel. Just need to drill holes in the base and connect the top to the aerator.
Useful if you can't get barrels (Used in the Permachar Kitchen Garden (PKG). The PKG was a prototype for this design. Imagine the half barrels as swales above the ground. Dig the swales slightly across contour. Optional biochar layer right at the bottom of the swale (used in the PKG barrels). Water collects in the swale base during rainfall and is stored in the Permafert/biochar layers. Irrigation (optional) tops up the water in the Permafert/biochar layers. The biochar (found in the base layer and Permafert) adsorbs water and slowly releases it for the plants and soil biota during drier periods.
This was dug in with a mattock and shovel after rain. If there is no water source accessible, you could increase the depth of the trenches after subsequent rainfall events. I got impatient and watered in the trenches from a watering hose. The trenches, when finished, should be about a foot deep. This will be my new veggie patch which will supplement the herbs grown in the PKG.
These are my Permafert midden pipes. They are 1m long 40mm PVC pipes with drill holes (using my largest drillpiece) on 4 sides of each pipe about 100mm apart. I buried the base about 100mm deep then used bricks to stabilise them. The idea is to pour water down them once the midden has been built to increase water content into the centre of the midden which will increase the micro-organism count.
I have rebuilt my middens using one of my current middens, silt from my fishpond (which should be full of Nitrogen) and cow manure that has been aged for 6 months and is now almost dry with no weeds. I'm hoping I can get IMOs from all three inputs. I will still turn over the middens every few days and pour wastewater down the pipes.