Gross sediment

[hillegom]

That is very detailed. Kudos to you for keeping such fine notes.
I have a question on your math.
In my opinion, what I remember from high school, the ratio 1:4 means, in this context, that for every one gallon of ro/di you make, you waste 4 gallons down the drain.
So I question you multiplying your final gallons by 4, should that not be multiplied by 5?
But I could be wrong, high school was very many years ago.