#### bitseriously

**Member**

Max Nitrate concentration (ppm, pre-WC, assuming stable tank) can be expressed as the weekly new nitrate buildup times the inverse of the percent of water changed.

*Note that for calculations, percent will be expressed as a decimal, or proportion of 1. Also, I can't do subscripts, so blue text is subscript.*

NO3max = NO3weekly increase x (1 ÷ WCamount)

__Examples:__

A. If your tank adds 5ppm/week of nitrates (cycle output minus plant uptake), and your change 1/4 (0.25) of your water in the same interval, your max NO3ppm will be 5 x 4 (4 being the inverse of 0.25) = 20ppm.

B. If your tank adds 10ppm/week of nitrates (double of above), and your change 1/2 (0.5) of your water in the same interval (also double of above), your max NO3ppm will be 10 x 2 (2 being the inverse of 0.5) = still 20ppm.

C. If your tank adds 10ppm/week of nitrates, and your change only 1/5 (0.2) of your water in the same interval, your max NO3ppm will be 10 x 5 (5 being the inverse of 0.2) = 50ppm.

D. If your tank adds 3ppm/week of nitrates, and your change 1/3 (0.33) of your water in the same interval, your max NO3ppm will be 3 x 3 (3 being the inverse of 0.33) = 9ppm.

Now, what are the practical applications of this? I have some ideas, but what say you?

Also, what do we name this principle/formula? Points for relevant acronyms!!

Eg.

__C__alculating

__I__nterval

__C__alculations (

__H__elpfully),

__L__ike n

__I__trates, by

__D__avid (my real name) = CICHLID