The Large 66Q Monotub Refill Kit restocks your 66-quart tub for another grow: two Premium 5-Grain spawn bags, 10 lbs of pasteurized Select Bulk Substrate, 6 new filter disks and a fresh black liner. Just add spores or liquid culture.
Made for the Grower's Select 66-quart tub from our Complete Large 66Q kit.
Refill for Large 66Q
Spawn +
4.6
33 ratings
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Thanks Midwest Grow kits.
J
John · October 13, 2026
Flush after flush
This thing has been producing flushes for the past 2 months and is still going!