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dosing a low tech tank on a 'Thames Water' supply with an allinone solution

a1Matt

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This thread is to share my allinone ferts strategy with others who are running a low tech tank with a Thames Water supply or similar (ph around 8, hard water, but low in magnesium).

I go more by the plants than the water report, but if your inclined to see how much e coli and clostridium you've drunk in recent years results are here: https://www.thameswater.co.uk/Help-and-Advice/Water-Quality/Check-the-water-quality-in-your-area

I use @JamesC DIY TPN(3) recipe as a baseline, full details can be found here:
http://www.theplantedtank.co.uk/allinone.htm

I then tweak it as follows:
Add double the amount of magnesium sulphate (34g in total).
Add double the amount of monopotassium phosphate (4.4g in total).
Add DTPA chelated iron at a 1:1 ratio with the trace (5g trace and 5g iron).

I bought 7% DTPA chelated iron off ebay, there are different percentages available, just get whatever is available/cheapest, we're not dosing precisely enough for it to matter.

Start with the Tropica recommended levels of dosing (as per James' website), then adjust up or down if needed.
IME dosing levels vary between 1/4 strength (dosing the weekly rate, but only once a month), to dosing double weekly.

Contrary to popular belief you can dose micros and macros at the same time, as long as the residual level of phosphate in the tank doesn't hit a certain threshold it will be fine.
If you do hit that threshold it means you are putting in more than you need anyway, so if that happens, just skip a week or so of dosing and/or do a large water change, then dose at a lower level when you resume.
(Remember, this strategy is aimed at low tech tanks where missing a week will not impact otherwise well fed plants.)

Watch the tank as you add the ferts, if you are adding too much you will see lots of white flecks when the ferts hit the water (the flecks are iron and phosphate precipitating out of solution and becoming unavailable to the plants). Don't confuse bubbles with flecks!

That covers dosing too much. You can tell if you are not dosing enough by observing whether the plants look deficient or have stopped growing.

There are lots of different dosing methods (I for one love going down the rabbit hole of trying different levels of this and that, the above recipe is a work in progress), and they all have their pros and cons, but as a one size fits all method for low tech, I can strongly recommend JamesC recipe. With or without my tweaks, it is fine to grow plants with.

A lot of us owe a debt to James for his work with fert mixes (I think there are even a few selling ferts commercially that used his research as a foundation for their product). If you see this James, thank you!
 

Angus

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Some good information to chew on matt, i've been looking at my iron and magnesium dosing, considering making a liquid mix with a sequested iron powder 'plant tonic' as i'm using london tap aswell and want to do it on a budget, nice post mate it is definitely reaffirming my thoughts.
 

a1Matt

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Thanks for the feedback Angus. If you do go ahead, post in the thread what recipe you come up with.

If your looking to experiment, then making up any solutions heavily diluted makes it easier to adjust dosing if needed. It also means you can finish the bottle quickly and try another combination. I like to make one months worth at a time as it gives enough time to monitor the results.
 

jameson_uk

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Just a few questions

Where did you source some ammonium nitrate? For obvious reasons people seem to be a little funny about selling it but I couldn't find any with a quick scan of Google.

What is your GH/KH?

How do you measure these amounts? Do you have very accurate scales or is there some sort of tsp conversion?

How do you what is low magnesium levels? My water company report doesn't mention mg but I do seem to remember Darrel saying that most UK water had low levels? (Or I could be making that up...)

I thought DTPA was only stable to ~ph 7.2? I presume it is working fine for you and you aren't seeing any iron deficiencies? I did find some EDDHA chelated iron https://uk.solufeed.com/products/chelates/solufeed-fe-70-eddha-regular) which is meant to be stable to about pH 9 but this is only available in kg boxes and not sure this would be ok to use? (@dw1305 would this be ok?)
 

a1Matt

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Just a few questions
emoji16.png
I'll do the best I can to answer :)

Where did you source some ammonium nitrate?

I used the recipe without ammonium nitrate - DIY TPN number 3.

What is your GH/KH
I dont test regularly. When I last did, out of the tap was around 16gh and 10kh.

How do you measure these amounts? Do you have very accurate scales or is there some sort of tsp conversion?
I use digital scales with 0.1g resolution. It's good enough for me. (If I was mixing my own micros then I would want 0.01g.) The Rotala butterfly calculators have teaspoon conversions.

How do you what is low magnesium levels? My water company report doesn't mention mg but I do seem to remember Darrel saying that most UK water had low levels? (Or I could be making that up...)
Experientally. I tried every combination of more/less of mg/ca. Came to the conclusion that my tap is high in Ca and low in Mg.
In this context, my definition of high or low is in relation to plant growth, not relative to a ppm value of the tap water. I.e. High means enough in the tap I never need to dose. Low means always need to dose. (Having said that, I did try no water changes once and after a few months saw a benefit from calcium dosing.) No scientific rigour here :eek:
I value the science, but I'm not kidding myself that I am capable of meaningful controlled studies at home. So I will learn from others who are better placed (Darrel, Clive, Tom Barr, JamesC, etc).

I also recall Darrel (and others) mentioning low mg water ;)

I thought DTPA was only stable to ~ph 7.2? I presume it is working fine for you and you aren't seeing any iron deficiencies?

I put off using it for years for that same reason. It works better than EDTA for sure. Maybe not perfect, but well enough to avoid iron deficiencies.

I did find some EDDHA chelated iron
My reading up on EDDHA showed that not many were using it and of those that tried most said it stained the water pink. I couldn't find any issues with it's safety.

So I've not tried it, but I may at some point.

If I do, I'd dose a small amount (in conjunction with the DTPA) to see if I can avoid staining. Say starting at 0.1ppm a week.

I'm sure you could get it in a smaller quantity than 1kg, probably from someone enterprising on ebay.

Ive heard the theory that different chelators keep the iron (or whatever else they are chelating) available for different lengths of time and that plants have to put more work in to get to the iron if it's in a stronger chelator. If that's true, having a mix of iron sources would be beneficial.

You can also buy trace mix where all the ingredients are chelated with DTPA instead of EDTA.

JamesC doesn't post online anymore (that I know of), but the last post I saw from him was to inform people that a DTPA mix had become available to buy in the UK.

So many things to try :)

I hope my reply helped somewhat.
 

X3NiTH

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The iron species I've used so far and from what I have read in papers discussing how the different chelators react under different pH conditions are -

Fe Gluconate - can last as little as two hours after dosing, least stable above pH6, similar to EDTA

Fe EDTA - stable to pH6, degrades above pH6, half life is at pH7, total degradation above ph7.6

Fe DTPA - stable to near pH7, degradation above pH7, half life is at pH7.5, total degradation at pH8.5.

I daily dose Fe @ 0.15ppm (Tank water RO/DI remineralised to KH9 GH8) using 0.1ppm Fe Gluconate and 0.05 Fe DTPA. Currently my daily dosing bottle is a mix of Flourish Comprehensive and Fe DPTA to get the above ratio then mixed together with Flourish Trace, I also add extra MnSO4 so that my daily dose works out at a Fe:Mn ratio of around 3:1.

In 24hr Fe titration testing (JBL test kit) the difference in readings I see are that the Fe Gluconate is gone within 24hrs while the assumed remaining Fe is Fe DTPA that reads about half its dose (0.025ppm, the JBL test barely reads the level).

My pH profile for CO₂ is pH7.6 - pH6.1, 8.5hr photoperiod then air pump on at lights off to vigorously off gas CO₂, tank is climbing above pH7 for at least 10hrs until it reaches around pH7.6 then the CO₂ comes back on for the next phase.

:)
 

jameson_uk

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Now not sure where to post but I was reading https://www.ukaps.org/forum/threads/ei-mix-with-tap-water.16388/ which says make the solution with whatever water you want but then we talk about iron coming out of solution within a time frame depending on pH. Would using DTPA be partly negated by putting it in tap water (mine ends up about pH 7.8 after everything has gassed off) so mixing up a 500ml batch would end up with no iron very quickly???
 

a1Matt

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The idea is that the ascorbic acid brings the ph down, keeping everything stable in solution.

I err on the side of caution and make it with RO. The longest I've had a batch last until it went cloudy was 18 months.

Just make sure you add the acid to lower the ph, before you add the trace and phosphates.

I add the acid first, then trace, then everything else, then phosphate last.

Apparently you can use other acids. Eg vinegar, lemon juice, etc. I've never tried though.
 

X3NiTH

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Yup, if the the pH climbs outside the pH range for the chelate it will let go of the Fe (other trace minerals are good up to about pH9 if the chelate is EDTA), which is why it is recommended to acidify the solution, Clive mentioned Hydrochloric or Sulphuric Acid, Tom mentioned Acetic Acid which is more readily available off the shelf (distilled vinegar), I've used Ascorbic Acid to the same effect. If using hard tap the recommendation is to boil it which destroys the KH thus making the pH of the water naturally lower, adding an acid helps lower it further. I use RO/DI for fert mixing but I still add an acid if I'm making an all-in-one solution just to be on the pH safe side.
 

a1Matt

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The iron species I've used so far and from what I have read in papers discussing how the different chelators react under different pH conditions are -

Fe Gluconate - can last as little as two hours after dosing, least stable above pH6, similar to EDTA

Fe EDTA - stable to pH6, degrades above pH6, half life is at pH7, total degradation above ph7.6

Fe DTPA - stable to near pH7, degradation above pH7, half life is at pH7.5, total degradation at pH8.5.

I daily dose Fe @ 0.15ppm (Tank water RO/DI remineralised to KH9 GH8) using 0.1ppm Fe Gluconate and 0.05 Fe DTPA. Currently my daily dosing bottle is a mix of Flourish Comprehensive and Fe DPTA to get the above ratio then mixed together with Flourish Trace, I also add extra MnSO4 so that my daily dose works out at a Fe:Mn ratio of around 3:1.

In 24hr Fe titration testing (JBL test kit) the difference in readings I see are that the Fe Gluconate is gone within 24hrs while the assumed remaining Fe is Fe DTPA that reads about half its dose (0.025ppm, the JBL test barely reads the level).

My pH profile for CO₂ is pH7.6 - pH6.1, 8.5hr photoperiod then air pump on at lights off to vigorously off gas CO₂, tank is climbing above pH7 for at least 10hrs until it reaches around pH7.6 then the CO₂ comes back on for the next phase.

:)

Thanks for sharing that :thumbup:

It would be interesting to see how uptake* in your tank compares to low tech tanks. (*edit - I probably shouldn't say uptake as we don't know what has happened to the iron. I guess I should say availability.)

You've got me considering buying a test kit for the first time in a long time :D

Either way I think it adds weight to dosing daily rather than weekly to ensure a sready supply of iron (and, to a lesser degree, maybe the other trace elements too?). As it happens I do dose daily, but more out of convenience (if I don't feed the plants at the same time as the fish I'm liable to forget to do it at all).
 
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X3NiTH

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Yeah I'd love to know the Fe uptake in the tank, can only get an idea by looking at the plants response to dosing these levels daily and since its 90% Bucephalandra in there makes it quite a challenge, I know it's working because the majority are producing new leaves normally in relation to the size of the plant and not teeny ones on a fat rhizome that just melt away. Since Buce leaves are very pale when new and colour up after they have unfurled it's hard to see iron deficiency until it's too late, from what I have seen if they starve of iron new leaves stop growing or fail to unfurl and the plant seneces them at the stem level.

The only thing I can be sure of is how much iron I'm adding by calculating the ppm for the dose I'm giving and that knowing that there is iron detected on titration testing post dosing. Not really interested in the accuracy of the test kit to my dose and what level is detected which is completely subjective according to how good I am or not at detecting shades of a colour and ascribing it a value from a printed comparative card. Strongly Positive colour change post dosing Very Weak Positive colour change pre dosing 24hrs later, control sample (fert front loaded remineralised RO/DI, no Fe or traces added) no colour change. That's all I learn from the test.

I have used EDTA chelated trace with Fe before to great effect in the pH range it is most effective in (sub pH 6) and have also seen it fail due to high pH (buffering water to higher KH from near zero KH). I have also done mixes with EDTA Trace with Fe and Fe DTPA together for use with high KH water, knowing the EDTA would drop the iron in higher pH tank water but still using it for the other traces which are stable until even higher pH, the DTPA provided the Fe (have mixed as both separate solutions and all-in-one mixes).

I've swapped to using Fe Gluconate provided by Flourish Comprehensive and Fe DTPA (11% powder, it is what I have to hand) because I don't really want to use EDTA at higher pH and have free EDTA binding up other nutrients when the iron has been freed from it or accumulating unbound in the tank.

I am not bashing EDTA here as I have said I have had great success with this (stem plants mainly) in pH it's more suitable for, my focus is I'm doing this for Buce, the rheophyte that can't fight, trying to understand in high light and near EI level dosing (always available nutrients) what they like and what they don't like, so far I know more about what they don't like than like, hence an expedition into understanding water chemistry and ppm of stuff that can be added in many various ways in an effort to have maximum availability for the plants in what they need and in the way that makes them respond positively.

So many different ways to do this that its like trying to skin Schrödinger's Cat.

:)
 

a1Matt

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I've only grown buces low tech (I gave up the gas before buces reached the hobby). I've found them quite forgiving at the low light levels I keep (albeit slow growing). I can imagine if you up the light they could get touchy quickly.

With regards to the unbound chelate building up (and bringing it back round to low tech allinone dosing strategies again), I do find that if I'm putting in a lot of ferts the tank does require more frequent water changes (judged by water odour and turbidity).

I don't profess to know why, I assume it's predominantly because the ferts feed more than just the plants (eg bacteria and archae) and more metabolism equals more waste equals more water changes. Lately, I've been wondering if unbound chelate adds to this. I wouldn't be surprised if after some time bacterial species develop that feed on it (that's their MO after all, mutations and colonies based on the environment).

I wonder if anyone has run tests that give an answer.

In practical terms it's all covered by good 'ol fashioned water changes anyway :)
 

X3NiTH

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Here's a study of EDTA.

https://www.researchgate.net/profil...mental-scrutiny.pdf?origin=publication_detail

With regards to bacteria eating EDTA there is this quote in the paper.
EDTA resistance to bacterial biodegradation is widely documented41-44. The compound is harmful to gram negative bacteria, causing the destruction of their outer membrane26-28.

At laboratory scale, biodegradation by enriched bacterial cultures has been achieved. Nörtemann5, suggested catabolic pathways of EDTA in bacteria, this approach considers uncomplexed EDTA entrance to the cell, and shows the loss of an acetyl group as the first step in this intracellular oxidation. However, it has been recently demonstrated that the bacterial strain DSM 9103 (located in the Rhizobium-Agrobacterium branch), degrades EDTA as a sole carbon source and it is able to perform the cellular uptake of the metallic complex EDTA-Ca (II), with intracellular calcium polyphosphates accumulation45. The identified bacterial strains with EDTA degrading abilities are all aerobic, gram negative bacteria46.

I think that strain of bacteria would be a challenge to source -
The only degradation achieved was with a strain of Agrobacterium sp. previously isolated from a nuclear waste disposal facility and of known EDTA degrading activity, and not with other related Agrobacterium strains.

:)
 

X3NiTH

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Buce hibernate on me in low tech, or at least that's what it feels like, in a tank with moderate CO₂ under PAR50 (calculated not measured) at the moment I'd be lucky if I get one leaf every month.
 

Konsa

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Hi
I have been growing few Buce varieties in low tech for about 2 years .In 2 of my tanks the light is on the strong side(one is 11w Arcadia strech on H22cm,second 55w pll lamp 4800lumen on H40cm) while the third is just right with 2 T8 18w(H40cm).Regular column dosing in all tanks.I found that the buces do best when attached to small lava rocks and roots get in substrate.Even with plain sand there is some mulm collection arround the base stone and they really benefit of it plus less stress if plant is moved.Once established with good root system they are very robust plant and grow few leaves a week from the multiple tips in high light and about a leaf in low light( still young plants tho) without CO2 enrichment and the leaves are well lived too in my conditions.
Regards Konsa
 

jameson_uk

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OK made the first batch tonight (with standard DTPA iron) and just a couple more questions...

Do you just add all the components to water in one go or do you add them in any particular order?
Do you do anything special to store the ingredients or are the bags they come in sufficient?
Does the resultant liquid need storing a dark dry place or does it not matter?
 

Konsa

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Hi
Defo store in dark place.My first all in one went funny (cloudy behind the tank with black background and minimum light in about a month and a half.Now second one in cupboard still good just in time the green colour (iron convertion from the acid)turns back to brown whatever that means )
Regards Konsa
 

a1Matt

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Do you just add all the components to water in one go or do you add them in any particular order?
In order. The exact order isn't important, but you don't want iron and phosphate mixed together until after the ph has been lowered.

So I add the ascorbic acid first, then trace, then iron.

Give it a stir/shake.

It looks dissolved at this point.

To be sure I add all the other ingredients except the phosphate, then another stir/shake (this gives more time for the acid, iron and trace to fully dissolve. I'm not fussed if the other ingredients are not dissolved fully).

Then add the phosphate last.

The warmer the water the quicker it all dissolves. So I often heat the water to lukewarm or so. (On the cooker, in a large pyrex jug, as that has a 500ml measure.)

Do you do anything special to store the ingredients or are the bags they come in sufficient?
Mine are decanted to plastic containers, then in a cardboard box, in the cupboard under the tank. This is for tidyness and ease of handling.

I don't know if the bags are sufficient.

At a guess, I think they are fine as long as they have an airtight seal. It is possible some of the ferts are photo sensitive though (I'm thinking of the chelators). Maybe someone who knows can weigh in.

Does the resultant liquid need storing a dark dry place or does it not matter?
Thanks @Konsa for answering this.

As well as keeping it in the dark, I also like to make it diluted (1 to 3 months worth), there is less worry about it going off then.

Having said that, I've had batches with no sign of mould after 18 months. Who knows what has degraded/precipitated in that time though.
 
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mooncake

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Thanks for this. I’m dealing with London water too, and will give it a read through as it’s a bit mind-boggling trying to suss what the best approach is.
 

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