Learning how worms work
The success of the Tiger Toilet will lie in the effective performance of the Tiger worms in the system.
These worms are used in toilets and for vermicompost because they’re robust and can withstand a wide range of conditions. But what factors will enable them to work the hardest in a system specially designed to meet the needs of poor people in developing countries?
To find out what makes them thrive and what their limits are, we’ve set up a lab at the Centre for Alternative Technology (CAT). We’ll test the conditions under which the worms will work best in the Tiger Toilets – the parameters within which they can live and reproduce happily and efficiently.
What we’re trying to find out
Drawing on available existing literature and expertise from around the world, we’ve designed a series of experiments to fill in the knowledge gaps and test Tiger worms in relation to our system. We want to know the ratios of human waste to treated waste that a Tiger Toilet could efficiently produce. In particular, we’re working to find out:
- Worms: how many are needed, their acclimatisation period, how much food material they need
- Bedding materials: where do worms like to live? Eg. in a layer of coir
- Tiger Toilet dimensions: what shape and size of tank works best for worms?
- Solids processing: the amount of vermicompost produced; the process of further breakdown by bacteria
- Effluent quality: does the system remove important pollutants and pathogens?
- Robustness: how do worms in a system like the Tiger Toilet react to shocks (eg. flooding, cleaning fluids)?
Our discoveries will inform the design process, so that Tiger Toilets can provide the ideal conditions for Tiger worms to work effectively. The learning will continue when we test prototype toilets later this year at CAT and in a sample target market, Tanzania’s principal city, Dar Es Salaam.
Help us make a difference
If you have knowledge or experience of working with Tiger worms, please get in touch. It could help us make a real difference to the lives of people in desperate need of sanitation.