So for anybody that's interested I managed to find some of these recipes, without having my hand held.
www.plantedtank.net
those recipes would be a good starting point, that thread is also bit old now and there is always new finding and new updates to share. we tested the Marcher Ratio starting with 0 TDS water, Marcel have done the same experiment, in that same video Vin has talked about Marcel's experiment, I believe Vin listed it as "half EI" which is also incorrect, because the formula is completely different from that. this is what Marcel have to say:
There was the following concentration of nutrients in That tank:
20 ppm CO2, 15 ppm NO3, 4.4 ppm NH4, 2.8 ppm PO4, 4.6 ppm K, 2.3 ppm Ca, 0.9 ppm Mg, 0.14 ppm Na, 12.8 ppm HCO3, 3.6 ppm SO4, 0.05 ppm Cl
(dGH = 0.54, dKH = 0.59, conductivity = 60 µS/cm)
I tested the same with the given formula and I too achieved the same good results using the exact same recipe and the chemicals, I tested it on several different plant which are hard to grow, I tried using different chemical for the same ratio and the results were different, taking out NH4 from the list and replacing with all NO3 didn't have the same results, Urea gave good results too but it was not same as when NH4 used in the recipe. during these tests I changed the ratio around, for example: changed the K from 1 ppm to 3, 5, 10 etc. and even though plant grew but some of them started to show the weird growth and some of them were stunted, made the same changes to the NO3 and same thing occurred. it was quite clear that every time I made the change to these ratio or chemicals, the plant reacted differently.
further more I did several other tests beside the Marchner ratio, the Marchner ratio test was Marcel Idea and it was based on "Marschner's Mineral Nutrition of Higher Plants" and these numbers are based on Terrestrial plant, not aquatic plant. there were time when we agreed or disagreed with each others, but we continued to explore more ideas. for me personally, even if you didn't follow the exact recipe, ratio etc. and started adding little urea/NH4 and reduce the overall NO3 in the water, you would achieve similar results if not perfect.
but what does those numbers tell us from the Marcher ratio?
K should be lower then N? Yes
do we need to add lots of Micro Nutrients? NO
do we need to add lot of Fe? NO (we never had to go over 0.1 Fe proxy using Tenso Cocktail) even at 3 ppm N weekly
do we need to have a good lights for coloration? YES
do we need to add lot of Fe to achieve the red color? NO
Tropica Follow lower K and Higher N for a reason. Tobi follow similar approach, Tobi is also using similar numbers to Marchner ratio for N, K, Ca, Mg. Tobi has very well explained the K causing issue and these issues are more related to this kinds of ratio rather than directly related to K itself. but let me tell you one thing, you will never be able to achieve the same ppm or use the same ratio in your aquarium due to water chemistry if you were using tap water. but at least you get an idea about the importance of these ratio.
under the following recipe:
#1 1000ml solution, 20 ml per 50 g
Dosed daily:
Urea (7 gram)
N 0.3450319
calcium nitrate (10 gram)
Ca 0.1793358
NO3 0.5549027
Magnesium nitrate (10 gram)
Mg 0.1001645
NO3 0.5110625
3 ppm PO4 weekly, 20-30 ppm K from GH Booster, very rich dosing of Micro/Fe with this ratio, I had very fast plant growth on many plant species, but not all plant grew well. some of them were severely stunted and some just turned black and disappeared. co2 diffused by reactor, max CO2.
#2 Tropica Plant Growth Specialized Modified Clone, used 1 to 3 ppm N weekly, used varies chemicals, switching from Non chelated to chelated, switching from N urea to N NH4 to N NO3 etc. following numbers dosed at such ratio produced great results, very fast growth, No algae. GH was less than 1-2 DGH, KH 0-0.5
N 1
P 0.074
Mg 0.3
K 0.77
S 0.68
Fe 0.0515
Mn 0.03
B 0.003
Cu 0.0044
Mo 0.0015
Zn 0.0015
#3 Marchner Ratio (starting with 0 tds water), dosed at 1-3 ppm N weekly. plant from Ammania family did even better under such condition, they did not stunt even at 3 ppm N proxy with Marchner, however they still got stunt with the recipe #2, #1 they wouldn't even survive.
N 1
P 0.133
K 0.668
Ca 0.334
Mg 0.133
S 0.066
Cl 0.0063
Fe: 0.01-0.02 (Tenso Cocktail Clone)
as I have explained earlier that most plant will continue to grow fine with any given ratio but you will experience some plant being stunted and some growing fast, some not growing at all. #2 and #3 should give you an idea about lean dosing and how I dose my tanks. if I were to dose #3 and raised the K from 0.66 to 5 ppm, I start to see Ammania twist and start to look weird. I have also seen people growing most of these plant without any issues even if they don't use the same ratio/recipe, but they all had one thing in common, they used high GH such as 5-6 DGH Ca,Mg, 0-2 KH, lower NO3, but higher Micro/Fe, take Marian Tank for example. I have seen people grow these plant with 5-6 DGH, 0-4 KH, decent Micro/Fe, K but no P or N added. they seems to keep the N quite low for some reason. but then how do you explain Ammania growing well even at 3 ppm N ? maybe because the N is in both form of Nitorgen N-NH4 and N-NO3? very likely. but at the same time once the doses were increased there was some plant damage, you can see it on the leaves. but we cannot ignore #3 and why did it produce such a great results, there is something about it, something special.
but do we have all the answers to all the questions? NO
are these above recipes or ratio going to solve all your problems? NO
Will EI going to solve all your problems? NO
is CO2 going to solve all your problems? NO
based on several experience, talking to others who conducted similar experience, gathering what people dose in there aquarium, it appear these people are dosing Lean or started switching to Lean dosing.
My thought on Lean Dosing is that lean dosing is an approach which is based on your plant needs rather than dosing excessive nutrients, if you have very little plants in your aquarium the need for daily dose should be very minimum. Lean dosing shouldn’t have any problem weather it is used under low or Under High Lights, weather its under 15 ppm CO2 or 30 ppm CO2. if you were to dose 3 ppm NO3 daily and only half of it is being used that would mean 0.34 ppm N daily, now lets say if you added 0.34 N from Urea/NH4 daily, you would have met all the plant needs while you have 0 NO3 in your water.
there is a book by Kramer that high Nitrates causes several issues, plant damage etc. this very well could be true, because most people who have great looking tanks keep very little NO3 in their water.
here's Barr tank with same plant under EI (am sure he have enough CO2)
Here's Mine Under Marchner #3 (15-20 ppm Co2)
like I said not all problems are CO2 related and not all plant will grow equal. Barr might be growing other plants well and so are the other people, but not all people are able to grow some of these plants, either they are stunted or not growing at all.