1.6L SubBox™ Bulk Substrate


Heard of the Monotub Tek?

If you have then you’ll know it’s how to turn grain spawn into a whole load of mushrooms!

We based our product idea on the well-known ‘Monotub Tek’, but made it simpler, cleaner, faster, modular and with less fuss. It trully is a game changer for anyone who has tried or wants to try their hands at monotub-style growing!

Excellent airflow and sized to fit our XL Grow Tent for easy mushroom fruiting.

SubBox™ has the perfect bulk substrate depth and fruiting area for achieving large harvests without the hassle.

100g of Organic Dry Coir within a HEPA-filtered 1600 SubBox™

Simple, effective and a better way for bulk mushroom growing, born during our Winter 2020 innovation break

Uniquely ours …as injection ported MycoPots/Boxes used to be til the competition came along!

Ok, enough of our ranting…


How to use?

  1. Add 500ml of water which will make the substrate expand to around 1 litres

  2. With a corner of the lid raised to allow steam to vent, microwave for 3mins 30secs

  3. Shake around (careful, hot!) and microwave for a final 3mins 30secs

  4. Click lid fully down and allow to cool to room temperature (a plastic bag is ideal to keep it clean whilst cooling)

  5. Remove lid then add 600ml of spawn (1x SpawnTubs)

  6. Mix evenly with clean hands and cover the exposed grain at the top with some of the hydrated coir

  7. Click lid down fully and leave to finish colonising in a warm area

  8. Once 100% colonised with healthy white mycelium, move to fruiting chamber* and introduce fruiting conditions

*Or purchase one of our XL Mushroom Grow Tents and 1500ml of Perlite to house the SubBox™, like the image below!

SubBox fruiting mushrooms

If you would prefer to use a very large fruiting chamber to have lots of SubBoxes in action, then you can calculate how many you need using the measurements below and how big the chamber is that you have

Growing Specs

  • Fruiting area: 37.5 sq inch
  • Substrate depth: 3.5″
  • Spawn to Substrate Ratio: 1:2 (Add 600ml of spawn to the prepared substrate)
  • Substrate Volume (when hydrated): 1000ml
  • Substrate Volume (with spawn added): 1600ml

SubBox™ Specs

  • Volume: 1600ml
  • Material: PP5
  • Dimensions: 7.5 x 5 x 3.5 inches
  • Autoclavable/Microwavable: Yes
  • Reusable: Yes
  • Filtration: HEPA 0.2μm

  Ask questions about this product here!

    Could i add a 1kg of colonised grain spawn to this?
  1. Q Could i add a 1kg of colonised grain spawn to this? answer now
    Asked on 3rd April 2021 1:17 am

    1KG of spawn is enough to do two of these.

  2. If using an XL grow tent does the sub box still need to be microwaved
  3. Q If using an XL grow tent does the sub box still need to be microwaved answer now
    Asked on 27th March 2021 2:28 pm

    It’s highly recommended, yes.

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