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foodchain
12-30-2013, 09:54 AM
IF 6 gallons of grow bed = 1 lb of fish. In optimal theory.

And grow bed is 1/2, 55 gallon drums. 2 ft x 3 ft x 1 ft = 6 cubic ft.
55/2 = 27.5 gallons. 27.5 gallons/6 gallons per 1 lb = 4.58 lbs
Each 1/2 barrel supporting in THEORY 4.58 lbs of fish.

It was easier to convert to gallons than cubic ft. But hopefully someone can follow this and confirm or correct me. Thanks in advance.

I opted not to count gallons of water, as stocking density will effect the concentration of dissolved solids/gallon. So it's inconsistent to count gallons. Add in plumbings, sumps, filters, etc and whatever else and it's not an accurate count anymore.

foodchain
12-31-2013, 12:44 PM
Anybody?

eddiemigue
01-01-2014, 05:15 PM
Hey foodchain,

Each GB will have 1/2*pi*r(sq)*h = 1/2*3.14*1*1*3 = 4.71cuft/GB, but you don't need this if you're looking at gallons.

Your math in gallons is correct, except that you may want to reduce your available volume since you are not likely to fill the GB to the top, or have water in contact with all the media.

foodchain
01-01-2014, 07:49 PM
Found the error. I calculated based on a rectangle, not a circle. Dang it.

However the end result, by switching to gallons over cubic feet got me within acceptable variance.

So the theory then, is that each 1/2 barrel should support between 4.58 and 4.71 lbs of fish. This will of course be effected by the type of fish, type of greens/plants, type of media, how many feet and what diameter pipes, and the total open surface area of the pond in conjuction with gas exchange.

And so my expansion continues.