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Seachem method of potassium dosing
- Thread starter MiZubov
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_Maq_
Member
Any idea what is rubidium and vanadium meant for?
John q
Member
Some literature suggests V is beneficial to plants in miniscule doses, but higher concentrations apparently cause plant death.
Rubidium, it seems plants can manage fine without it.
I wonder if the inclusion in the product isn't necessarily intentional on seachem's part, just something that came up when it got analysed. (Maybe from the water they mix the fertiliser in or a contaminant from the other ingredients?)
Either way to the average Joe on the street it probably looks snazzy having these fancy elements listed on the label, even if in reality they have little to no benefits to the plants.
depends but most likely not. those numbers are what most people like to dose, so I used that for my example.
Hi all,
cheers Darrel
They are definitely "impurities". You can <"analyse for trace metals"> using Inductively Coupled Plasma / Mass Spectrophotometry (ICP / MS).
cheers Darrel
_Maq_
Member
If this is the case, then the list of elements is definitely selective. They are mentioned to look "scientific", I suspect.
Years ago, I too believed that proper nutrition does the trick. So I ventured enthusiastically into those "potentially beneficial elements". Unsurprisingly, it was a completely wasted effort. Trace elements are omnipresent - in trace amounts. I've established that even dosing nickel and molybdenum makes no difference, and quit them.
There are two elements, though, which I have not discarded from my attention, yet - sodium and silicone. I still believe that silicone may benefit ferns and grasses, and I suspect sodium may be of some significance for Ammannia genus and possibly others. I've been dosing these quite regularly for years and I haven't found any manifest results.
In general, I think the importance of nutrition is rather overestimated. Typically, the tank as a whole is in trouble, and people ask which nutrient is missing. In most cases, other factors are at play. I believe that microbes are the bosses of our tanks.
Hi all,
Eventually I settled on Magnesium (Mg) as my <"missing element">, you get obvious nutrient deficiency symptoms and a pretty quick recovery when magnesium stops being <"Liebig's Limiting Nutrient">.
In terms of plant growth and yield, you can just <"limit the amount of nitrogen"> (N) you add.
cheers Darrel
Yes the same for me. Years ago I used to make up "missing nutrient" hydroponic growing solutions for work, but I pretty quickly realised that they didn't "work" for most of the trace elements, presumably because it was impossible to totally exclude them from the solutions and <"any contamination was enough"> to stop inhibition of plant growth.
Eventually I settled on Magnesium (Mg) as my <"missing element">, you get obvious nutrient deficiency symptoms and a pretty quick recovery when magnesium stops being <"Liebig's Limiting Nutrient">.
In terms of plant growth and yield, you can just <"limit the amount of nitrogen"> (N) you add.
cheers Darrel
Wookii
Member
Yes, in a high tech tank with a lot of fast growing stem plants and high light, even higher with tanks lots of floating plants in addition.
Edit: Scratch that I was thinking 20ppm, which is possible, 30ppm maybe not so easily.
_Maq_
Member
You know, I'm rather sceptical of this question. I don't say yes or no, I really don't know. I'm sure that it's far from possible in low-tech.
The only hobbyist I know who has nitrate ISE electrode is myself. Colorimetric tests for nitrates are notoriously unreliable. So, pardon my question, but how do you know?
If we permit consumption 3 mg/L NO3- per day, that - using Redfield ratio - corresponds to consumption 14 mg/L CO2 per day at least.
To me, it seems rather too much. But maybe I'm mistaken and someone knows better? Did anyone try to measure it experimentally?
Wookii
Member
Well in a previous tank, very heavily planted and lots of floating plants covering the surface I was dosing EI NO3 levels (20ppm) weekly, and I measured with a couple of different test kits (different manufacturers).
Now I know the test kits are horrendously unreliable, Nitrate ones in particular, but I wasn’t interested in a PPM value, I just wanted to know if I had a lot, some, or none in the water column. Both test kits returned zero values.
I was farming off a 2 litre jug full of floating plants every week or so, so I imagine it was mainly those sucking all the nutrients from the water column.
Also worth bearing in mind that, when Tom Barr came up with EI dosing, the PPM dosing targets he came up with were based on the absolute maximum uptake he observed in his tanks under optimum conditions.
That being said, I’m not sure he had a surface covered in floating plants with prefect access to light and 400ppm CO2.
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John q
Member
Well we both know the answer to that and he came to the conclusion of 10ppm No3 maximum uptake per week.
That said i don't believe those tests included floating plants.
Is a maximum tank and all a tank contains consumption of 20ppm nitrate p/w beyond the realms of possibility, I honestly don't know.
Sounds like you need to pick up where Marcel left off and set up a test tank @_Maq_
Wow! So interesting! How did you come to this conclusion? Did you specifically testing?
Thanks a lot!
_Maq_
Member
I don't inject CO2. This makes a qualitative difference because microbes influence measured nitrogen substantially. I've made such tests a couple of years ago. Without plants. My aim was to measure/prove denitrification. Nitrates in water column fluctuated depending on sugar addition. More sugar -> less nitrogen, less phosphates. Apparently the nutrients were sequestered in organic matter. Then I quit sugar additions. It took weeks until the phosphates reached original level. Nitrogen (TIN) never did. Apparently some of it was lost due denitrification, but the results were not clear enough.
What it did show clearly, though, that depending on the state of microbial community, a lot of nitrogen may be tied in organic mass, both live & dead. This makes measuring plants' consumption difficult.
_Maq_
Member
Scientific literature, plant physiology. There are known rules valid for all plants.
I wonder if the concern of plants using all the nitrogen (or whichever nutrient) is valid. The way I see it, plants will act differently at different concentrations, it isn't a binary status (either there is nitrogen left or not). So maybe if you add 20ppm nitrates, it could be valid to impose that the water levels never go lower than 10ppm, or something like that.
I appreciate that things are always much more complex than what they look, but does this make sense?
I appreciate that things are always much more complex than what they look, but does this make sense?
_Maq_
Member
It does, but as far as I know it works rather differently. Plants do possess different regimes for nutrient uptake. Maybe not for all of them but definitely for nitrogen. But they switch to higher sensitivity at concentrations which from our perspective - units of mg/L - are very close to zero. (Even "lean" dosing refers to "hypereutrofic" in natural waters classification.)
Yet there's one more important fact. Cultured plants often show signs of given nutrient deficiency because they are genetically programmed to ripe quickly. Natural forms, in contrast, often simply quit growing. They are accustomed to periods of starvation or otherwise unfavorable conditions (drought, cold, lack of some nutrients).
How much these general rules apply to aquatic plants of our tanks remains open to observation and practice. Our tanks differ in many ways from natural habitats and we often lack an explanation.
MichaelJ
Member
Nothing much to add except for a reminder....
My 60p soft water
I actually do have some green slimy thread algae which is rather annoying, but since it's so thin it's almost invisible until you get up close. 😂 Aha! I knew it wasn't perfect! :lol: ... we'll have that fixed for you soon enough...
www.ukaps.org
As you can tell from @plantnoobdude's results, plants don't need a lot of fertilizers even with high tech... personally and from experience, I don't think it necessarily hurts to dose higher levels of N, P, K it's just unnecessary... but if you feel your particular plants have "extraordinary needs" or your tank conditions requires it, due to hard alkaline water etc., then go for it
Absolutely not, unless you're injecting exorbitant amounts of CO2 and your plant mass is beyond ridiculously demanding - and inherently very fast growing... or if maybe your trying making to make a living from selling aquatic plants.
As @John q said - which is spot on. I doubt the contents is anything but collateral from the water source they are using... think about it, if you add the recommended amount of Sachem Trace, which is 6.6ml twice per week (13.2 ml) per 100 liter of water, it will give you an amount roughly equal to 3 PARTS PER TRILLION of Vanadium* ... its like if you would add 3 grams of salt to a million liters of water, which is roughly half the size of an Olympic Sized Swimming pool, to raise the salinity... Sachem Trace probably contains Gold (Au), Titanium (Ti) or perhaps even Plutonium (Pu) as well in similar amounts, but the marketing department just didn't have the shameless audacity to include those in the table of contents... yet!
*Vanadium can be used to make steel alloys, for use in space vehicles, nuclear reactors and aircraft carriers, etc. Yup! Highly relevant for aquarium plants! ... also, Vanadium has been shown to lower total "bad" cholesterol in humans ... so it could possibly benefit your fish as well if you feed them a lot of fried food
Cheers,
Michael
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One important thing to consider when we are talking about consumption of Nitrogen is to consider weather it's coming from NH4 or NO3, or both.
NH4 is rather rapidly consumed, especially the floaters consume it very quickly in comparison to NO3. If most of the N is coming from NH4, it will certainly be consumed at higher quantities. In another word, if you were to add 1 ppm N from NH4 vs NO3, you will find that plant growth is much superior when using NH4 and there is hardly any buildup of NO3. On the other hand if you were add 1 ppm N from NO3, the nitrogen consumption is rather slow or low. The end result is usually high level of NO3 in the water. Plant also shows poor coloration
Consumption of 6 to 7 ppm N per week is more possible when nitrogen is present in NH4 form, it is less likely to happen if the nitrogen is present in NO3 form. But it would be extremely difficult to measure such event accurately, Because there are many other factors at play.
NH4 is rather rapidly consumed, especially the floaters consume it very quickly in comparison to NO3. If most of the N is coming from NH4, it will certainly be consumed at higher quantities. In another word, if you were to add 1 ppm N from NH4 vs NO3, you will find that plant growth is much superior when using NH4 and there is hardly any buildup of NO3. On the other hand if you were add 1 ppm N from NO3, the nitrogen consumption is rather slow or low. The end result is usually high level of NO3 in the water. Plant also shows poor coloration
Consumption of 6 to 7 ppm N per week is more possible when nitrogen is present in NH4 form, it is less likely to happen if the nitrogen is present in NO3 form. But it would be extremely difficult to measure such event accurately, Because there are many other factors at play.
