2 comments

  • schiffern 5 hours ago

    More: https://news.ubc.ca/2025/09/ubc-launches-worlds-first-mushro...

    I predict this will need a method of preventing houseflies from laying eggs on the material, which will happen within hours. This is the main reason why portable toilets use the blue liquid. Having housefly maggots crawling out of the device will end any real-world experimental trial rather quickly.

    Typical fly lifecycle: https://www.the-piedpiper.co.uk/th6a.htm

    At a minimum, I would recommend using a fine (noseeum) mesh screen along any air vent or intake paths, and using a tightly-sealed and gasketed toilet seat.

    Signage should indicate that the lid must be closed after use, maybe even with a sensor. Having a soft-close seat and lid will likely increase compliance and improve the user experience.

    Flies go faster than even rapid airflow, so airflow alone won't keep them out. Odor mitigation will reduce flies, but not entirely eliminate them. And even "waterless flush" systems can have residue where flies will lay eggs.

    I would consider incorporating agricultural fly-paper rolls mounted inside the commode compartment itself, to quickly catch any flies that get past the toilet seat lid, before they can lay eggs. For another layer of protection (and again better experience) you probably want traps inside the toilet stall as well.

    The agricultural flypaper (CatchMaster XL or similar) usually comes on a 30cm x 100m roll, and it's by far the cheapest and most effective option. Avoid funnel traps, which attract flies but have poor catching efficiency.

    This needn't be complex or expensive. Trap designs can be very simple, like this: https://www.youtube.com/watch?v=pFHJJOdOzK8 The material comes on a roll, so it can also be automated.

    Wonderful effort and initiative by the entire team, thanks for sharing! Just trying to maybe "head off at the pass" foreseeable challenges that might crop up. I look forward to following this project with great interest.

    • lioeters 4 hours ago

      Sounds like you have real-life experience with composting toilets. Good to hear practical tips, since I started studying this topic to consider for a living situation with limited water.

      The link for more info was great too. I followed it to a page with technical details about the separation of liquid and solids, diagrams of the building and the recycling process.

      Biogenic Architecture Lab - Botanical MycoToilet https://www.biogenicarch.ca/bg-mycotoilet