As a general guideline, not as waring of toxicity, EI suggest 30ppm or so, you do not want to go much beyond say 40ppm and if so, then modify the dosing routine.
Tap water NO3, fish waste can add to the NO3 as well.
If you are in that target range, then modify the dose accordingly.
While you might hit 60ppm, 70ppm etc, there's no need to go that high either.
There's also no rule suggesting not modifying it and not testing, you certainly may if you want and not waste the KNO3, but it's(dry ferts) so cheap, most do not bother since they hate test kits so much.
But a little testing can tweak things for folks if they chose.
The only issue arises is when folks claim you must test, or that 40ppm is "bad", "toxic", " will cause algae" etc.
That's BS.
We can and have tested it and shown that's BS.
But that also does not mean you should never test or use common sense, that's why there's a range listed in the article I wrote.
Test kits, water changes, etc can be used to modify and adjust the ranges targeted.
EI just suggests a method that does not require them, it does not say you should not use them, subtle but a big difference.
The larger issue that EI addresses, and the main purpose is non limiting nutrients, and that "Excess" or non limiting nutrients for plants, does not cause, induce, or exacerbate algae.
This is where it differs radically from PMDD, from which it derived and started. PMDD is leaner and was developed using lower light systems. Both EI and PMDD add and maintain NPK, Traces etc for plants, in that respect, they are the same.
Paul Sears use to say to add PO4 if it got too low, he knew that it would strongly limit plant growth.
If you added more light, then you dose more. I chose this path and realized I needed to dose a lot more to make sure things did not run out over time. Daily was not possible due to weekend work and travel. So I need to guess for 2-3days and could do large water changes.
If you chose not to do water changes, then you can balance with test kits, PMDD also suggested this as well, but also suggested water changes also, mostly as a way to have a safety valve or if things got away from you too much. I know Paul Sears, discussed PO4 test, algae etc, and where he got some of the background for that method. Otherwise, one is not better than another, it's just a trade off. EI can go that same route if you want to use test kits, but you can do water changes to avoid them also. The trade off to maintain a ppm range, and the ppm range itself are the real issues. Both add the same ferts.
So folks can go all test kits, or all water changes, but many do some of both.
Which PMDD and my old article shortly there after PMDD was popular:
http://www.barrreport.com/estimative-in ... eters.html
I also suggest some better test kits which we knew faired well with calibration standards. How do you know about that unless you did a lot of testing?
😉
Regards,
Tom Barr