Container Size vs Actual Amount of Medium

Indoor Growing
1

I got to thinking, and thought about the Conversion of Cubic Feet into Gallons.

A Bale of Promix BX is 3.8 cu/ft. or 28.4 GALLONS of Medium. Ok.

So, a Bale of Promix will basically fill 2 x 17.5 - 20 Gallon Totes, and then another 1/3-1/2 of another one. At that rate, it seems a Bale is roughly say 45 gallons of soil, considering the 2x 20 gallon containers are filled to about 2-4 inches from being topped off.

So, when I fill a 17.5-20 gallon container, there is actually about 11-12 Gallons of soil. Say 22 gallons of soil in the 2 large containers, and another 6 gallons, in the 1/3-1/2 full container.
So, if I am using organic fertilizer, and am supposed to use X Amount/TBLSP of said fertilizer, per gallon of soil. One must be very careful, and determine the actual amount of Medium, vs how full x Size pot appears.
A 5 gallon container, of Promix BX would most likely have about 55%-60% of what the actual container size is.

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2

If I’m remember right a trade gallon is actually 0.7 of a gallon.

That’s a pain watering per gallon.

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3

I think its actually .777 :stuck_out_tongue_closed_eyes:

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4

I use the metric system anyway.

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5

If one knows what a compressed 3.8 cu/ft Bale of Promix BX, Peat Moss, or the like looks like???

That is roughly 28 Gallons of Medium. Keep in mind, it is compressed out the wazoo, and will greatly expand. That amount will fill up at least 2 x 20 gallon containers, and 1/3-1/2 of another. Makes it look to have about 50 gallons or so of medium, when it only has 28.4 gallons

So, when one puts this type of Medium, into a container, in expanded condition, it takes up roughly Half the space of what the container says it will hold. Say an advertised 20 gallon grow bag, will hold about 9.1 gallons of Promix BX, if tis true to specs. So this means if one is measuring fertilizer, that requires TBLSP/TSP, per gallon of soil, and you make the mistake of using enough fertilizer in a 10 gallon grow bag, to fertilize 10 gallons of medium, when in reality, you are using 2x the amount of fertilizer required, as the medium amount, is vastly overrated. Double.