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Mushroom Substrate Hydration Calculator
Getting your substrate hydration right is one of the most critical steps in mushroom cultivation. Too dry, and your mycelium stalls. Too wet, and you invite bacterial contamination.
Substrate Hydration Calculator
Calculate exact water and dry material needed for your mushroom grow bags.
Hydration Recipe
Dry Substrate Needed100.00 kg
Water Needed150.00 Liters
Total Batch Weight250.00 kg
How to Use This Calculator
This calculator uses the standard mycological hydration formula. To use it:
- Enter your bag count: How many grow bags do you want to make?
- Enter dry weight: How much dry material (e.g. hardwood sawdust and soy hulls) do you want in each bag?
- Set the ratio: The standard for most wood-loving species (like Oyster and Lion's Mane) is 60% water to 40% dry material.
Why Hydration Matters
Mycelium needs moisture to break down the substrate and transport nutrients. However, standing water (field capacity exceeded) creates anaerobic conditions at the bottom of your bag, leading to "sour rot" and bacterial blotch.
Common Hydration Targets
- Masters Mix (50/50 HWFP/Soy Hulls): 60% Hydration
- Straw (Oysters): 65-70% Hydration
- Rye Grain Spawn: 50% Hydration