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Mushroom Bags (SacO2, MicroBags)

4.80 out of 5
(5 customer reviews)

£3£685 (incl. VAT)

Premium polypropylene MicroSac mushroom grow bags by SacO2. A revolutionary depth-filtration system provides perfect, evenly distributed gas exchange via multiple parallel filtered seams without drying out the substrate or spawn. Making them the most advanced breathing bags on the market.

Available for spawn or substrate production. Uniquely different to classic unicorn bags which use surface membrane filtration, the MicroSac offers depth-filtration (much like a HEPA filter).

Whilst a little more expensive, in our side-by-side tests, they have shown to offer noticeably faster colonisation time.

  • Fully Autoclaveable: Guaranteed up to 123°C (253°F).
  • No Dry-Out Zones: Limited contact between filter and bag contents minimises dehydration zone under the filter area.
  • Filter Distribution: Multiple filter strips on each bag ensures even and consistent air exchange throughout entire bag.
  • Application Specific: Different filter widths for spawn bags and substrate bags provide optimum air exchange for different applications.
  • Physical Strength: Made from thick, durable polypropylene, providing excellent strength and tear resistance.
  • Heat Sealing: Can be heat sealed using a standard strip heat-sealer.
  • Development: Designed and developed by national spawn supply company, used industry wide.
  • Completely Transparent: Optimal visibility throughout the entire growing stage.

* Please check bag specifications below or view the SacO2 brochure here before ordering.

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£3£685 (incl. VAT)

Purchase today to earn 3-685 POINTS worth £0.15-£34.25 to redeem on your next order.
Purchase today to earn 3-685 POINTS worth £0.15-£34.25 to redeem on your next order.

Frequently Bought Together

Spawn Bag Specifications

Medium Spawn Bag
Medium Spawn Bag

Size: Medium
Product Code: PP75/BEH4+1/V22-49
Film thickness: 75 μm
Number of filter strips front: 1
Number of filter strips back: 4
Bottom gusset: yes
Height: 49 cm (20.9 inch)
Width: 22 cm (8.7 inch)

Large Spawn Bag Mushroom Cultivation
Large Spawn Bag

Size: Large
Product Code: PP75/BEH6/V37-53
Film thickness: 75 μm
Number of filter strips: 6
Bottom gusset: yes
Height: 53 cm (20.9 inch)
Width: 37 cm (14.6 inch)

Substrate Bag Specification

Medium Substrate Filtered Mushroom Bag
Medium Substrate Bag

Size: Medium
Product Code: PP75/SEH6/V32-49
Film thickness: 75 μm
Number of filter strips: 6
Bottom gusset: yes
Height: 49 cm (19.3 inch)
Width: 32 cm (12.6 inch)

Large Mushroom Substrate Filtered Bag
Large Substrate Bag

Size: Large
Product Code: PP50/SEU4/V40-51
Film thickness: 50 μm
Number of filter strips: 4
Bottom gusset: yes
Height: 51 cm (15.7 inch)
Width: 40 cm (15.7 inch)

SacO2 Videos

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5 reviews for Mushroom Bags (SacO2, MicroBags)

  1. 5 out of 5

    Steve Price

    great quality bags which work, worth the little extra in price in my opinion with decent savings when buying bulk amounts. Thank you

  2. 5 out of 5


    I think the previous two reviews covered it all. Great bags which have improvements over traditional unicorn bags. Will continue to use these in the future.

  3. 5 out of 5

    Julie Omar

    better value than unicorn bags at 20% off… ordered 100 for the time being but if you keep the 20% offer going I'll buy more in the future. Arrived well packaged 2 days later

  4. 5 out of 5

    Martin Riley

    Quality grow bags at a good price. I share the same experience as 'Martin the mushroom man', increased colonization times more uniform across the bag and less contamination issues (on 50 bag grow)

    A little something to add: I've had times where I've punctured holes in filter in unicorn bags when handling. These bags seem to mitigate this issue due to their different filtration design.

    For me they are worth the small price increase. – An innovative approach to the standard mushroom grow bags


  5. 4 out of 5

    Martin the mushroom man

    Got sent a couple of these bags in a recent order as a bonus gift to try out (thank you very much!), I wasn't sure what to expect as I've never heard of them before. But, I can confirm the following from a direct A/B grow comparison using golden oyster strain on hydrated rye grain:

    * Colonisation speeds in these bags increase by ~20%
    * Colonisation is noticeably more consistent presumably from the increased areas of filtration/air exchange.
    * Quality and strength of bags are similar, they also heat-seal well using an impulse heat sealer.
    * I've had contamination problems before if filter has got wet during colonisation of Unicorn bags, it seems to draw in contamination. The design of these bags mean there is increased depth of filter medium so I'm hoping these will be better in the future, but cannot draw accurate conclusions from a small growth trial.
    * These are a little more expensive than unicorn bags.

    In conclusion: thanks for allowing me to trial them, if the price came down a little to be more in line with Unicorn bags, I'd likely order them instead.

    Thanks and hope this is helpful for some.

    • Paul T. (Founder)

      Hi Martin!

      Many thanks for leaving such a great review, it's great to have feedback from our customers and no doubt you would have helped many other people out there.

      We use these bags exclusively at Hear Me Raw for our mushroom blocks and spawn bags (there are two different type for people wondering). Since moving over, we've noted a significant reduction in contaminated bags as well as a quicker colonisation time around 20% as you noted. For us, the slight increase in price is worth it.

      We will wait to see what the demand is for the bags, if it's high enough to reach another price-point from our supplier, we might be able to offer them at a better price. Watch this space!


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