posted 8 years ago
If you're able to collect 21,000 liters (5,548 gallons) of grey water per month, I'm thinking your first step aught to be trying to conserve water. Even the average house in the USA (which is quite wasteful) doesn't produce anywhere near that much grey water per month.
FWIW My wife and I use less than 6,000 liters (~1,560 gallons) per month(in just the house, not the garden), we harvest about 1/2 of that as grey water. We cold probably get a little more, but diminishing returns make it not worth the cost/effort.
My opinions are barely worth the paper they are written on here, but hopefully they can spark some new ideas, or at least a different train of thought