@"Gerrit"#p174 I like the idea of a water based liquid (just like Rabaey's) so I checked out the [Nutrisorb Trace Minerals](https://www.biocare.co.uk/nutrisorbr-liquid-trace-minerals-15ml) ingredients:

  • 1. Purified Water,
  • 2. Sodium Borate,
  • 3. Preservative (Citric Acid),
  • 4. Chromium Chloride,
  • 5. Manganese Sulphate,
  • 6. Sodium Molybdate,
  • 7. Sodium Selenite.
    •

    So, when compared with [Rabaey et al](https://www.researchgate.net/publication/43500477_Continuous_microbial_fuel_cells_convert_carbohydrates_to_electricity) they are missing:

  • 1. iron,
  • 2. zinc,
  • 3. calcium,
  • 4. copper,
  • 5. nickel &
  • 6. cobalt.
    •

    And add:

  • 1. citric acid,
  • 2. chromium &
  • 3. selenium.