Targeting Potassium

[eminor]

I tried everything to get perfect co2, i believe my co2 is now perfect, flow is everywhere, every plant is moving nicely. I did EI in most tank which make plant grow quicker but not better for sure, i tried kind of lean dosing but i always added potassium because i saw ADA approach which was my mistake. Few times ago @_Maq_ wrote on a topic of mine about ratio about Mg:Ca:K ratio, since that day i changed my mind which was set that plant need tons of nutrients to grow no matter what it need to be plenty. I changed my mind since that response and tried to go leaner on the potassium, i always added more than Mg and Ca. I though it was iron deficiency but when i added iron, the deficiency was still there in RO water...

Hetheranthera Zosterifolia is an easy plant which had so much deficiency problems in my tanks, so i reduced the potassium below the Ca/Mg since then plants are growing fine, no stunted growth, i'm not and expert and i don't know if that post is usefull but i trully believe that @_Maq_ is getting in the right direction at least for me.

Happi also converted me to lean dosing, that guy have the most healthy and colorful plant i've ever seen. I can be wrong, maybe clive or other will prove me, but i doubt EI user can get such colors

 

[xZaiox]

For what it's worth, just like @eminor above, I also have some anecdotal data to add to this thread. I've had issues with warped growth on my hygrophila siamensis 53b for a while now. Many people in previous posts seemed to think it was an iron deficiency. This was while dosing EI levels of iron, even upto 1ppm with different chelators (DTPA, EDDHA, EDDHSA) and fe gluconate. It continued to showed warped growth. I read posts from Maq and Happi about this Ca:Mg:K ratio and decided I'd give it a go. Lo and behold, it fixed the warped growth.

Spoiler: Warped Growth

Spoiler: Healthier Growth

I should add though, I still have some slight warping on my h.polysperma rosanervig. I've also noticed that my h.compacta doesn't seem as happy in less potassium dosing. My take away is that this lowered level may not work for all plants, but it absolutely seems to work for some. There is definitely something to ratios and excesses of potassium levels.

 

[_Maq_]

My take away is that this lowered level may not work for all plants, but it absolutely seems to work for some. There is definitely something to ratios and excesses of potassium levels.

I too came to a conclusion that this is not the time to make conclusions, and more research on this "ratio" topic is required. I'll definitely perform more tests once I'll finish my current job.
What is clear so far is that the simple rule "all cations in excess" does not guarantee a success.

 

[xZaiox]

I too came to a conclusion that this is not the time to make conclusions, and more research on this "ratio" topic is required. I'll definitely perform more tests once I'll finish my current job.
What is clear so far is that the simple rule "all cations in excess" does not guarantee a success.

You've been in the hobby longer than I have, but from my experience so far, I absolutely agree. I'm going to continue with lowered potassium dosing for a while and see if my hygrophila compacta springs back to health - I'm hoping that maybe it's just used to higher levels, and that it can adjust to the lowered levels now? If not, then I plan to eventually start slowly increasing the potassium levels and see if I can find a level where all of the plants are happy.

I'm definitely seeing very positive results from the lowered dosing though, it's only really the h.compacta that has reacted negatively.

 

[plantnoobdude]

You've been in the hobby longer than I have, but from my experience so far, I absolutely agree. I'm going to continue with lowered potassium dosing for a while and see if my hygrophila compacta springs back to health - I'm hoping that maybe it's just used to higher levels, and that it can adjust to the lowered levels now? If not, then I plan to eventually start slowly increasing the potassium levels and see if I can find a level where all of the plants are happy.

I'm definitely seeing very positive results from the lowered dosing though, it's only really the h.compacta that has reacted negatively.

In my experience, the ratio of calcium/magnesium to iron is very important aswell. With lower GH you can get away with much less iron. At my lowest I was dosing 0.016 Fe weekly, which is a tiny fraction of EI.

 

[xZaiox]

In my experience, the ratio of calcium/magnesium to iron is very important aswell. With lower GH you can get away with much less iron. At my lowest I was dosing 0.016 Fe weekly, which is a tiny fraction of EI.

Interesting, do you have a rough estimation for the level of iron in proportion to Ca/Mg? I'm currently dosing 0.5ppm. My plants are at long last greening up, I plan to gradually reduce the dosage after a while to find the minimum effective level, but as of right now, I'm just going to let them get their fill for a few weeks.

 

[plantnoobdude]

300:1, is the lowest ratio I can arrive at.
30Ca 0.1 Fe DTPA works well aslong as water is free of co3 or high Po4
5 Ca : 0.016 Fe again works well aslong as water is soft and lean. The ratio is again 300:1
From numerous experiments, 300:1 is where I find the line is.

 

[_Maq_]

the ratio of calcium/magnesium to iron is very important aswell.

THAT never occurred to me. I'll keep it in mind when designing my formulas and observe the results.

 

[bazz]

Good evening all,
I have a question or 2. Obviously I've seen photos of most of your aquariums and those that I have I know what you are growing but...

Question 1, Would you guys and girls advocate the above water parameters (and lean dosing, ratios etc) for all tanks, whether for stems only or purely Crypts, Swords and Epiphytes?

Question 2, To have the full equation all in one sentence, is anyone/all willing to provide your full ideal ratios of all the nutrients, i.e. N P K Ca Mg Fe Mn B Cu Mo Co Ni?

The reason I am asking is because since joining UKAPS in 2009 I've been pretty much consistently been dosing full EI.
I'm quietly confident of moving home within the next 6 months to a year and will most certainly be acquiring a much larger aquarium. I've been running my present tank for 2 years now and would like to spend the remaining time testing minimal amounts (within reason) of what I'm adding to my tank. It is 230l high tech and is brimming with Crypts, Buces, Jave Fern and Anubius only, and for reference is currently running at GH4 and KH 0.5.

The relevance to this thread is obviously because Potassium in particular is going to be massively reduced.

Many thanks for persevering with the above,
bazz

 

[plantnoobdude]

Crypts, Swords and Epiphytes?

These plants are not sensitive at all and will grow well without much consideration. I would suggest something like 1/4 EI up to half EI.

 

[xZaiox]

Good evening all,
Question 1, Would you guys and girls advocate the above water parameters (and lean dosing, ratios etc) for all tanks, whether for stems only or purely Crypts, Swords and Epiphytes?

So far, with my reduced potassium dosing, the ONLY plant that has reacted negatively has been hygrophila compacta. I have a few echindorus species, one sword, multiple different crypt species and various epiphytes including bucephelandra kedagang, 3 different anubius species, and 2 java fern species (regular and trident). All of the aforementioned species (except h.compacta) haven't been bothered whatsoever by the lowered potassium dosing.

My tank is looking far healthier now than it ever has.

 

[_Maq_]

Crypts, Swords and Epiphytes

These plants are not sensitive at all and will grow well without much consideration.

Interestingly - and annoyingly - crypts and buces are not growing well for me. They remain small, dwarfed, creating new leaves just as small as the old ones.
I keep them in eight tanks in total, incl. my experimental Micurins, sharply differing conditions, lean/huge, acidic/alkaline, various ratios... nothing works for me.
So, please note that there are some champions who manage to be unsuccessful with ordinary crypts and buces. 😕

 

[erwin123]

Interestingly - and annoyingly - crypts and buces are not growing well for me. They remain small, dwarfed, creating new leaves just as small as the old ones.
I keep them in eight tanks in total, incl. my experimental Micurins, sharply differing conditions, lean/huge, acidic/alkaline, various ratios... nothing works for me.
So, please note that there are some champions who manage to be unsuccessful with ordinary crypts and buces. 😕

There is actually nothing wrong with small leaves. It may well just be an adaptation to environmental conditions. What I would pay attention to is the colour of the leaves (assuming your Buces / Crypts aren't just the plain green ones), whether there are any holes in the leaves, and the rate of growth/size of the rhizome.

 

[John q]

The reason I am asking is because since joining UKAPS in 2009 I've been pretty much consistently been dosing full EI.
I'm quietly confident of moving home within the next 6 months to a year and will most certainly be acquiring a much larger aquarium. I've been running my present tank for 2 years now and would like to spend the remaining time testing minimal amounts (within reason) of what I'm adding to my tank.

I think the simplest advice would be to follow the tried and tested method of slowly reducing ei standard ratios. Its not ground breaking stuff, but will allow you to reduce dosing, without making things complicated.

Reduce full ei by 10% every 2 or 3 weeks, watch the plants and if at any point issues materialise, then step back up to the previous dose.

Like I said it won't win you the Nobel prize, but it's a simple effective way of lowering the ferts we add.

 

[bazz]

Cheers for the suggestions everyone but kind of what I am endeavouring to achieve is minimal TDS coupled with an interest in nutrient quantities/ratios.
The difference between these ratios e.g. dosing full EI or using TSN is astronomical.
Just slowly reducing EI until my Crypts start melting is not really telling me which nutrient is deficient and would therefore result in increasing all nutrients back up again. To slowly reduce/increase the nutrients individually using this method could take years.
I suppose the answer to one of my own questions is to slowly reduce ferts targeting a TSN clone.
Anyway, I'm looking forward to punching some new figures into the formidable IFC Aquarium Fertilizer Calculator.
Cheers and thanks, back to targeting Potassium.
bazz

 

[_Maq_]

The difference between these ratios e.g. dosing full EI or using TSN is astronomical.

Astronomical differences there are, indeed. But the results cannot be easily linked to amounts and ratios. It's a science, after all, agronomists study these things for centuries. And similarly, in our tanks, multiple variables may affect the results.
That is why I didn't provide you with my preferred ratios/amounts. I'm not going to pretend that I've arrived to some kind of ultimate truth. Still only learning. Others use very different formulas, and the results are similar for all of us - mostly positive, perhaps, yet always many questions remain.
You might find this interesting reading. You'll see what it looks like trying to find a bit better formula...😀

 

[bazz]

You might find this interesting reading. You'll see what it looks like trying to find a bit better formula...😀

I'm already following it mate 👍

 

[palcente]

So far, with my reduced potassium dosing, the ONLY plant that has reacted negatively has been hygrophila compacta.

What happened and do you have pictures before and after?

What was the start K level and what was it lowered to ?

What other plants did you have in the tank and how did they react?

I also have this plant and I am in the process of dropping potassium from 100+ ppm to as much as I can. So far I have not noticed any difference with this plant, I have however seen reaction from other plants.

It would be good to document this, as it is working.

Thanks,
Matt

 

[xZaiox]

What happened and do you have pictures before and after?

I've attached 2 pics below named 'before' and 'after'. The before pic was taken quite a long time ago tbh, it was even before a rescape I did... but it's growth has mostly been the same until the potassium change. You can see some of the lower leaves aren't exactly healthy, ignore that, I was having fluctuating co2 at the time. You can see all the new leaves on it look very luscious, healthy and big. In the 'after' pic, you can see that the leaves don't quite look fully deployed, there is some warping on most of the leaves.

What was the start K level and what was it lowered to ?

I've changed my K levels quite a lot, the plant grew as the 'before' pic anywhere between 20-60ppm of K. The 'after' pic is now that I have lowered the K to 5ppm.

What other plants did you have in the tank and how did they react?

I also have hygrophilia siamensis 53b, hygrophilia polysperma rosanervig, monte carlo, ludwigia glandulosa, limnophila hippuridoides, rotala h'ra, bucephelandra kedagang, anubias (mini, petite and coin), java ferns (regular and trident), pogostemon erectus, s.repens, and various cryptcorynes, echinodorus' and a sword plant. All of these have either not reacted or showed improve growth.

I also have this plant and I am in the process of dropping potassium from 100+ ppm to as much as I can. So far I have not noticed any difference with this plant, I have however seen reaction from other plants.

From my understanding, this is a gross overdose. Plants take up more nitrogen than potassium, and if you were to dose 30ppm of NO3 (standard EI), then this provides 6.78N, so potassium shouldn't need to exceed this number (6.78). Someone more knowledgeable correct me if I'm wrong on this please... but I guess this is where it gets more complicated if certain ratios are important... i.e the plants don't take up anywhere near as much magnesium as potassium, yet it seems it may benefit certain plants to have the potassium be lower... this is beyond my pay grade I can't imagine any tank that needs anywhere near 100ppm of K though.

 

[_Maq_]

the plants don't take up anywhere near as much magnesium as potassium, yet it seems it may benefit certain plants to have the potassium be lower

There are two kinds of transporters in cytoplasmatic membrane dedicated to these cations. One is specific for potassium, another can take in K+, Na+, Mg2+, or Ca2+. So, the latter is unspecific and competition may occur, while K+ uptake is safely secured through dedicated transporter.
Through this scheme, plants reflect two facts:
(a) their demand for cations is K > Ca >= Mg (>>>> Na),
(b) in nature, these cations are most often present like this: Ca >= Na > Mg > K.
The whole thing is more complicated, but basically,

• plentiful calcium may hinder uptake of magnesium, but uptake of potassium remains safe,
• plentiful potassium may hinder uptake of both calcium & magnesium.

Obviously, we can expect variability among species thanks to their adaptations to original natural habitats. Par example, plants stemming from Pantanal region probably never face high concentrations of Ca & Mg. On the other hand, in southern China and Indochina, many regions are rich in calcite/magnesite (CaCO3, MgCO3) and plants from these regions live in waters rich in Ca & Mg.
The bad news is that scientific literature is rich in papers dealing with economically significant plants, but very limited in research of nutrient uptake of submerged plants.