You can and should modify EI, that's the main point, you start at an upper reference point, then reduce(or not), there is no assumed or demonstrated risk.
PPS, PMDD, non CO2, whatever commercial brand, sediment sources, they all add the same things.
So you are not going to get away from that.
Planted tanks are about 50% light 40% CO2 (if used) and only 10% nutrient dosing.
The dosing method is rarely the problem unless you simply are not addign enough or adding everything you should be, in other words, excess ferts poise no risk.
Most of the real risk in the assumptions aquarist place on nutrients being all important, when in fact, light and CO2 are and cause most of the mismanagement, and certainly 99% of all fish death/mortality is caused not from nutrients, rather, CO2.
The best solution might be to go to the sediment rich methods+ water column, in case you space out and forget to dose, there is a redundant back up (I do this on most of my own tanks) + low light (folks add and waste too much light and then complain they have issues with nutrients and CO2).
If you want to test and fiddle with 11 different nutrients and dose some other ratio to the water column, I doubt you will gain anything. You might run into some correlation and ascribe the results to some thing entirely unrelated, this happens often.
The best way to rule out ferts, is from a non limiting reference, that's all EI is, from there, you can reduce it down slowly, watch the plants to reduce water changes etc. I have tanks that go 2-3 weeks without any water changes. EI was never intended to be treated as rigid as many assume.
Nor was PMDD, and it's cousin, PMDD+PO4.......from which EI evolved.
Over/under dosing a little is fine and poses no risk. Those that believe it does clearly have not mastered CO2/light and have dependency in their system.
If the CO2 is poor, then no dosing method will prevent issues unless the nutrient limitation is greater than the CO2 limitation. This might get rid of the algae, but it certainly does not grow the plants efficiency or get the most out of the lighting/CO2 etc.
All dosing routines add the same stuff, whatever gets enough ferts in there for a given rate of growth is really all that matters. Still, EI is just a simple method to rule out nutrient issues. It's also about as simple as dosing can be made using the cheap DIY salts.
But without test kits, we can simply reduce and dose less and watch plants, this is not a method really, more just a tweak, wether you start low and increase, or start at a non limiting level and reduce, they should both end at the same point. Water changes offer the hobbyist a simple way to reset things. With decent observational skills, you should be able to go long times without water changes, but I still do them to stay on top of things. Some tanks do fine, others seem to need the water changes more for the goal.
You can avoid water changes/test kits for months, and dosing for the most part by going non CO2, still, fish food is still "dosing". Or dose lightly once a week. Plants grow all for the same reasons in every "method". Plants will still grow(non CO2 or not), but the rates they grow and the light use efficiency changes greatly. This is the key difference.
Since all growth starts with light, management is best done by adjusting and limiting light, then CO2 and nutrients/sediment nutrients/algae issues are far easier.
Step back and look at the bigger picture, not focus strongly on dosing or its micromanagement. I've never seen that be particularly productive for anyone trying to get to their goal.
Regards,
Tom Barr
that was the last straw for me. your posts are so full of bad information, i can no longer take you seriously. i'm sorry. this is just ridiculous. i saw the videos of your tanks, they are beautiful. i honestly dont know how you did it because there are so much mis-information in what you post
