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Possibilities of substrates are endless. To determine the expansion and absorption capacity of a new substrate, you can use the method below. For obvious reasons, it is clever to automate these calculations.
Take a sample of 100ml of dry substrate and weigh it
100ml sec = 50g
By soaking or cooking, saturate the substrate with water. Let drain 15 minutes and measure the new volume
100ml sec = 200ml wet
Expansion ratio = Wet volume ÷ Dry volume
200/100 = 2
Weigh the wet sample, and determine the amount of water
50g dry = 125g wet
Volume of water absorbed (per 100ml) = Wet weight - Dry weight
125 - 50 = 75g = 75ml1)
Conversion for 1 liter of dry substrate
75ml water / 0.1L dry = 750ml / L dry
Calculate the amount of substrate necessary
X = Number of one-liter pots
Substrate need = (X ÷ Expansion ratio) * 70%2)
Substrate need = (X/2) * 0.70
Calculate the water requirement
Water need = Water absorption (per liter) * Volume of substrate moistened
Water need = 750 *((X/2) * 0.70)