Aquadream;79586 said:
I have been using this special N fertilizer recipe for few months by now. In my case it does work somewhat better than just KNO3, but I am not sure why. my observation is that this recipe works better in aquariums with very soft water KH 1-2, GH 2-3. In water with higher KH and GH it does not have so much effect.
My small theory is that everyday supply of small amounts of Ca++ and Mg++ could benefit some plant species. I tested that theory with K+. If I supply the weekly amount of K+ at once in the beginning of the week by the end of the week I get K+ deficiency symptoms. If I supply smaller amounts of K+ every day then I do not get any K+ related problems. In both cases I am talking about the same weekly amount of K+ of 30ppm.
My guess is that the other cations would be more accessible if supplied every day or at least few times per week to prevent possible participation into insoluble or inaccessible compounds.
Well of course it will work better where folks
do not use Gh booster.
Which as far as I can tell, has been the case with many that have used it.
Whether the Ca and Mg come from sulfate or NO3 really do not matter and K+ is independent as long as it is not limiting.
You still have SO4 from K2SO4
You still have Ca, Mg and NO3.
Whether it's dry form makes a difference or not is baloney.
Same for the ratios.
Once in the water.....they are dissolved.
I do not buy this............
You can add GH booster and should see the same effect, if not, then it is something else that was overlooked.
Unless the salts are not dissolving and there is some sort of "magic", this should be true.
If you go from say 30ppm down to say 5ppm, vs simply staying at 30ppm to 20ppm, then that might be why.......
I dose 2-3x a week, I do not try and push weekly dosing.
With higher rates of growth, it seems 2-3x a week is the min for dosing, EI does/suggest this, but some go daily also with EI.
If you dose daily vs 1x a week, of course you will see improvement.
I have no issue with special N, but it's simply adding a GH booster to the N vs GH booster alone(which should be added if you use very soft water and in many cases even if not).
I honestly cannot see how there's any difference other than Liebig's law going on here, the salt fertilizers ALL DISSOLVE into the same things once in the water.
As long as the absolute levels do not fall to limiting values or where the plants have to adapt enzymatically due to wide flux of ppm's in the water(1x a week say vs 2-3x a week), this should and does not make any difference.
I've moved ferts around and over wider ranges than most hobbyists, I can see no evidence to support any of this. My tanks/plants can only getting through scaping and general care, not adding light/CO2 or some special fertilizer ratio/routine.
For maintaining stable ppm's , this works over a much wider range in the upper ranges vs the lower ranges, so if you like to add barely enough, or keep the dosing very lean to lean, then you might see some enzymatic effects and adaptations, but that is due to limiting and running things lean, not due to a special magic.
As you approach a limitation......you have to start dosing more carefully and daily etc. Every growth curve, dosing method, Liebig's law predicts this.
I have soft water, GH of 2 and KH of 1. I dose 2x a week mostly except for Traces, which has some Mg. I dose K2SO4/CaSO4/MgSO4 as Gh booster 2x a week.
I use KH2PO4 and KNO3 otherwise. Now if they went with the Urea/NH4 aspect, then that would make a difference...........as NH4+ NO4 vs NO3 might make some difference, there is some support for that, but curiously....the folks using this dosing have abandoned that, and only are using NO3 alone.
They were just limited prior to using this and did not use GH booster is all. They need to go back and see if the GH booster does the same effect, and it better..........otherwise they made a mistake somewhere.
As I am adding K+ as Gh booster, and as KNO3(much more than Special N), and as KH2PO4(also a lot more than many of the dosing folks that use special N), I have little issue, as long as the levels do not fall below 10-20ppm, I'm good.
How does one get K+ deficiency at 10-20ppm?
I can see say 5ppm or less etc......so then daily becomes important perhaps.........but at say 20-30ppm...........there is little difference between 20 and 30ppm.