One tank built so far in 2018 using concrete rings instead of an IBC tank to contain the vermicomposting ecosystem and a water-based reed bed treatment system instead of the greenfilter bed.
We are in Tulikup, Gianyar, Bali, Indonesia. People can visit. They can contact through whatsapp number +628123644446.
We are now building a second one using a rammed earth structure/tank. This second one will be way more interesting as it will have a proper control tank after the phyto treatment so that we can clearly analyse the output.
Here is a quick description of how I built the first one.
Two prefab concrete tubes of 100 cm diameter and 50 cm height were digged into the ground. The top surface of the tubes is at ground level.
Layers inside the concrete tubes, from bottom to top:
1. A drain has been placed at the bottom of the tubes, covered by a plastic mesh (1 cm mesh size) . All the bottom of the tube was plastered with cement with a 3% sloop to direct all black water towards drain.
2. A 5/10 cm layer of 3 to 5 cm gravel.
3. A 0.75 mm synthetic mesh
4. Layers of carbon supplies: rice straw, rice hulls, coarse wood chips of up to 10 by 3 cm, cartoon.
This last layer filled the tank up to 75/80 cm of the concrete tubes height.
The drain takes the filtered water to a phytotreatment tank of 2 by 2 meters side and 1 m deep. It’s is filled with river stones and volcanic/lava stones. Planted with reed, taro, banana.
Not sure of the worms we used. I just bought some at the bird shop.
The toilets are used by 6 persons.
The result has been great. Zero maintenance and zero problem. Pictures attached here show how there is nothing left of the big wood chips. I have just returned a scope of the tank organic matter and we can see there the many worms living there. There must be a huge total amount of them! I shall add some new wood chips soon!