I basically agree with everything that's been said. The need for most hobbyists to follow a certain "method" seems to cause a lot confusion IMO. People seem to be focused on exacting calculations as well as squabbling over numbers, levels and... the big one, "does too much really cause algae".
There's nothing wrong with wanting exact numbers and questioning things. However, many hobbyists fail to learn the "why we dose what we dose
" lesson. Once we understand that it gets really easy and it just makes sense.
The range for error is huge if you do regular water changes which happens to be the single most influencing factor for nutrient management. Something to remember,... that "fine line" where nutrients become limiting is finite. When you hit it, plants become limited. Above that line...nutrient Nirvana.
I see hobbyists trying to fine tune their dosing everyday. Nearly every one of them do at least monthly water changes. My question is, why would we ever want to approach that "line"? There's nothing to gain from dosing just above limitation. We can dose 5 times (probably much more) what we normally dose in most cases without issue. Big margin for error there. So all we need to do is stay well above that limiting point and we're all good right?
Think about it this way. Water changes and dosing alone can be used for nutrient calculations. Forget plant density, light levels, CO2 or any other factor. PROVIDED
we do regular water changes. If water changes eliminate build up then why can't we dose out low tech tanks the same dose?
The answer is we can!
As I said I hate "method" names. However, if we look past the "how to" of the EI method we can see the beauty. Dosing non-limiting nutrients has been around for nearly a century folks. That's the most efficient fertilizing method and probably always will be.