# Why exactly do we dose EI on alternate days? . . .



## Wookii (21 Sep 2020)

I've never been able to find an accurate explanation for this.

I understand the need to store concentrated micro and macro mixes separately to try and avoid the iron and phosphate reaction and resulting precipitation (though of course there are techniques for AIO solutions that we are all aware of), but when dosing EI, there will (or should) always be a prevailing levels of PO4 in the water column, so why does it make any difference if we dose micros and macros on alternate days, vs everyday at half the alternate day dose?

I've read some people say that the iron/phosphate reaction can occur at tank level concentrations, and others say that is nonsense and in tank concentrations are too low for that to happen on any problematic scale. Even then, if the reaction does occur in tank, is that not an argument for ensuring each is topped up daily?

I appreciate it might be wise to wait an hour or so between the doses to allow thorough mixing of the first dose with the aquarium water, so does the alternate day dosing really just stem from convenience for manual dosing?

If so, as we are now in a world where electronic dosers are available to the masses for reasonable cost, would timed daily dosing not create better in tank stability than the alternate day dosing?


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## dw1305 (21 Sep 2020)

Hi all, 





Wookii said:


> If so, as we are now in a world where electronic dosers are available to the masses for reasonable cost, would timed daily dosing not create better in tank stability than the alternate day dosing?


Ideally you probably would dose every day if you wanted optimal plant growth.

In commercial tomato culture (<"using rockwool">) you feed twice a day, and tomato farming doesn't have a lot of margin, so that is usually a pretty good indication that this is the most efficient method.

My guess is that it doesn't make much practical difference for the micro (trace) elements, the plants just really require "some" rather than "none".

If you were confident that you weren't going to have a doser malfunction (that dumped lots of fertiliser in your tank) it would also open up the potential for using <"urea ( CO(NH₂)₂ ) as a nitrogen source">. As well as being <"very cheap"> (and <"not a potential explosive">) urea allows you to add nitrogen (N) on its own.

Even though phosphorus (P) is a macro-element plants need an order of magnitude less of it than they do carbon (C), nitrogen or potassium.

Because most phosphate compounds are insoluble in hard, oxygenated water many plant have adaptations that allow them to effectively scavenge any available PO4--- ions. It is a bit like the adaptation that allows _Ceratophyllum demersum &Vallisneria_ spp etc. to use HCO3- as a carbon source.

cheers Darrel


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## Wookii (21 Sep 2020)

dw1305 said:


> Hi all, Ideally you probably would dose every day if you wanted optimal plant growth.
> 
> In commercial tomato culture (<"using rockwool">) you feed twice a day, and tomato farming doesn't have a lot of margin, so that is usually a pretty good indication that this is the most efficient method.
> 
> ...



Thanks as always Darrel, great reply. What are your thoughts on the phosphate and iron reaction/precipitation at typical in-tank concentrations?


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## dw1305 (21 Sep 2020)

Hi all, 





Wookii said:


> What are your thoughts on the phosphate and iron reaction/precipitation at typical in-tank concentrations?


I'm pretty sure that some people have seen precipitation occur, possibly because they were adding iron gluconate etc . You really need @X3NiTH to comment, they are <"a proper chemist">.

In terms of iron (Fe) you could definitely get around any problems by adding a chelator that is more effective at higher pH levels. I like the <"pink tint"> approach, but I have a pretty <"_laissez faire">_ attitude to <"fertilisers etc">, and just want some plant growth.

cheers Darrel


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## sparkyweasel (21 Sep 2020)

EI was developed to be simple and foolproof. By specifying alternate dosing it removes the possibility of a problem that _might _occur in _some _tanks, depending on many variables. If you change it there's no certainty that you won't have any problem. That's not a reason for not trying it to see, but it's a reason for the original EI method advising the alternate day method which more or less guarantees success.


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## X3NiTH (21 Sep 2020)

dw1305 said:


> You really need @X3NiTH to comment, they are <"a proper chemist">.



I wish, I don’t have single chemistry qualification to my name because I’m/was crap at maths and school was a bad place for me to learn, ‘too easily distracted’ was a bane on every single school report card that my father would punish me for which was cruel as he was exactly this way himself (himself crap at school but exceptionally brilliant in the things he took interest in), Too easily distracted’ is a horrible put down way to phrase ‘Interested in Everything’.

Now that I’ve humbled myself I hopefully can answer the question!

At standard doses for tank volume you should really only see precipitation if you were to dump the entirety of an Iron dose in one go into the water (brown/green clear liquid takes on a milky appearance), it would depend on how strongly bound the chelate was at the specific pH when it’s dosed, the effect would be localised and quickly stop visibly reacting with present phosphate as the total concentration of the iron becomes more dilute as it diffuses through the water column, you will lose some of the total iron but not all and if dosed everyday or every other day you are unlikely to end up with deficiencies (unless your mega dosing phosphate through extra added ferts or excess fish food).

If you do see milkiness when dosing iron it may be worth either diluting the concentrate further to reduce total concentration for the dose size or drip it in slowly using a doser (I dose @ 1ml per min and it goes in drop by drop, complete diffusion with no apparent precipitation).

I find there is Zero point in regular testing for total levels as long as they are going in regularly, you can test at the beginning to get an idea of the longevity of the chelate you are using for Iron at the pH levels you have in the tank.

I use mainly Gluconate and DTPA as Fe chelates as my pH is above neutral all the time, the gluconate can be gone quite quickly, I’ve read somewhere within an hour depending on how much light there is, I haven’t bothered to test for this because the plants should have scavenged what they need for the day before the main dose is all gone. The DTPA on the other hand constitutes one third of my blend and it’s half life is considerably longer than gluconate, When first testing the effect of this blend at above neutral pH I was detecting less than Half the total amount of Iron dosed for DTPA 24Hrs later (assumption that the gluconated chelate is 100% broken down). This shows that as soon as the chelate degrades the free Iron will react with whatever it can bind with and drop out of the water column, things it can turn into that make the Iron unavailable are Phosphates, Oxides and Carbonates, how much would depend on their total concentration in the receiving water (ending up amongst that brown floc at the bottom of the canister filter hopefully).

You’ll note that that having said all of the above I’ve not really considered plant uptake as an effect for loss of Iron from the water column only hoped for it, you can’t test for this without destruction of the plant so you are left with making observations that new growth is not pale and iron deficient (Darrells’ Duckweed Index will give you the fastest visual results for determining white new growth).

Takeaways are if you see precipitation takes steps to mitigate this by increasing the dosing time or dilute the concentration and dose more, if your out of pH range for your chelate then switch to one that is more suitable.

Dose Often!


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## Luketendo (22 Sep 2020)

Oddly enough the EI fert I mentioned on that other thread has everything mixed in all in one bottle, but still says dose every other day. I decided just to dose everyday instead since I don't want to be trying to remember if I dosed yesterday etc...


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## sparkyweasel (22 Sep 2020)

X3NiTH said:


> ‘too easily distracted’


= bad teaching. But of course the teachers blame their pupils for their poor teaching skills.


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## dcurzon (22 Sep 2020)

X3NiTH said:


> Too easily distracted’ is a horrible put down way to phrase ‘Interested in Everything’.



Thank you just for this


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## Zeus. (22 Sep 2020)

X3NiTH said:


> Dose Often!



I even took this one step further with auto doser, why dose macros x3 week and Micros x3 a week ? there are seven days in the week. So I dose micros 4 times a week dosing less on micro day but the weekly total yield is the same. Plus with my tap water dosing Macros after WC seemed silly as my tap water with a 50% WC was putting in about 10 ppm NO3


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## Wookii (22 Sep 2020)

Indeed @Zeus. - the Jebao doser I have can only do alternate days anyway, it doesn't have a weekly scheduler - so I dose every day, micros/macros on alternate days, essentially on a 14 day cycle. But then I do automated  daily 25% water changes also, so it works well without any issues with water change timing. 

It just really occurred to me, and was the purpose of this thread, if we're using an auto-doser, why are we doing alternate days - if thats a hang-over from manual dosing days - when we can schedule a dose whenever we like and achieve better consistency and stability of the nutrients in the water column.

Further to @X3NiTH 's excellent post above, I personally see no clouding at all in my tank when I dose micros, and I dose double PO4 in the macro mix to help keep GSA at bay, and also double Fe as I add DTPA to my micro mix. If we also consider that the dose usually goes in after the CO2 has kicked in, so the pH will have already dropped below pH 7.0 and remain there for the photo period, then I think there is little need to dose micros and macros on alternate days.

I will run a test this weekend and dose a full micros dose an hour after a full macro dose and see if I get any clouding in a still tank. If I don't then when I rescape in a couple of weeks I'll likely re-program the doser to dose both daily an hour apart.


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## Zeus. (22 Sep 2020)

Wookii said:


> if we're using an auto-doser, why are we doing alternate days - if thats a hang-over from manual dosing days - when we can schedule a dose whenever we like and achieve better consistency and stability of the nutrients in the water column.



Yes I think it is a hangover from manual/dry dosing days. As it took effort. With an auto doser theres no effort needed once setup.

Just thinking about it and a cant think of a good reason why we cant dose Macros and Micros on the same day - say Macros at noon and Micros at midnight. This would take the little and often just one step further and should make for a more stable/balanced system.

Then if using an AOI fert and dosing x7 a week - why dose it all at once (if your auto doser allows) split it up into a few doses over the day !!! Makes sense after what  @Z3NiTh posted


X3NiTH said:


> increasing the dosing time or dilute the concentration and dose more



Spreading the dose over the day is increasing dosing time


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## Zeus. (22 Sep 2020)

Zeus. said:


> Then if using an AOI fert and dosing x7 a week - why dose it all at once (if your auto doser allows) split it up into a few doses over the day !!!


Dont need to think about that one as its a 'no brainer' IMO

so was 10ml once a day (ignore the label 'macro' as its just a label)





Now 1ml x10 a day two hours apart




Think it will be better also as I am dosing Urea as the source of Nitrogen in this tank - little and often to very little more often


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## Geoffrey Rea (22 Sep 2020)

Interesting. The takeaway from @X3NiTH ’s post that grabbed attention here was:




X3NiTH said:


> You’ll note that that having said all of the above I’ve not really considered plant uptake




Consider @X3NiTH to be very wise in this self observation. Taking things to their logical confusion is great theory but... what about your outcome?
Your plants are your end users, what remains in the water column, ascertained by any particular measurement at any single point in time, isn’t really useful in telling you how your end users are doing. Striving for consistency at all times? Why? What evidence exists to say this is superior compared to alternate day dosing of the full daily volume of either macro or micro nutrients at once for your plants?

Being blunt, the estimative index is drum roll.... estimative. Any argument based on the effectiveness of varying methods of nutrient deployment would have to consider the effectiveness of any single plant species to uptake nutrients. Or, just look at the plants or duckweed or [insert choice here]. Things that could be messing up your chi other than nutrient input; lighting, plant location within tank, flow, competing algae’s, human error.

All things considered instinct says it’s what you consistently do over the months that matters, rather than the chosen method day to day.

The glaring hole in the conversation here is _what are you trying to influence? _

Healthy growth? Fast growth? Slow growth? Particular plant form under specific lighting and nutrient availability?

If it’s simply growing plants without deficiencies in a simple and successful manner:




sparkyweasel said:


> EI was developed to be simple and foolproof.



Each to their own. Eat twenty four small meals a day or three meals a day. Either way you won’t go hungry.

Also still waiting to see this massively iron deficient tank on UKAPS that is EI dosed with EDTA chelated iron. Every time, and I can’t stress this enough, *every time* a customer came in claiming iron deficiency it was either a) an incorrect deficiency guess or b) they messed up their mixing with phosphate and nitrate with their macro mix. Suffice to say I remain very skeptical that iron deficiency is prevalent in EI dosed tanks whether or not it is theorised that a majority of what is put in precipitates out amongst all the complex, largely untestable chemistry taking place in an aquarium. 

Iron is and always will be a micro nutrient. EDTA, DPTA, EDDHA.... Try not dosing it at all for several weeks, take weekly photos. It will take an age for iron deficiency to appear across the entire tank, especially if you use tap water for water changes. Highly suspect ‘groupthink’ has more to do with aquarists obsessing about iron than any real empirical evidence.


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## Zeus. (22 Sep 2020)

ceg4048 said:


> Hello,
> This is one of those situations where we make life more complicated for ourselves with very little to show for it.
> 
> Iron is a micronutrient, which means the plant only needs microscopic amounts of iron. About one hour after you have dosed iron, the plant has already taken up it's fill. Of course it's easy to pummel the plant with more iron than it needs without any ill effects, but why bother? Why spend more money and effort for specialized chelation when it is already overkill with the less efficient chelated methods? I really doubt you will see any benefit.
> ...




Taking the plunge again, Modified my Macro/Micro dosing on 500l so they get Macros and Micros every four hours with a two hour delay between the the Macro and Micro dose with the same weekly yield in ppms


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## Wookii (22 Sep 2020)

Geoffrey Rea said:


> Interesting. The takeaway from @X3NiTH ’s post that grabbed attention here was:
> 
> Consider @X3NiTH to be very wise in this self observation. Taking things to their logical confusion is great theory but... what about your outcome?
> Your plants are your end users, what remains in the water column, ascertained by any particular measurement at any single point in time, isn’t really useful in telling you how your end users are doing. Striving for consistency at all times? Why? What evidence exists to say this is superior compared to alternate day dosing of the full daily volume of either macro or micro nutrients at once for your plants?
> ...



Turning the question on its head though Geoff, what is the reason not to dose daily? What is the benefit of dosing alternate days instead, particularly if that involves more complicated doser set-up and programming? Surely, beyond anything else, dosing daily simply reduces the likelihood of any deficiency occurring since every photoperiod has all nutrients dosed just before.




Geoffrey Rea said:


> If it’s simply growing plants without deficiencies in a simple and successful manner:
> 
> Each to their own. Eat twenty four small meals a day or three meals a day. Either way you won’t go hungry.
> 
> ...



Your experience of all this is obviously far greater than mine, or indeed many others on here, but I had what was diagnosed as an iron deficiency on the new growth of my Hygrophila Polysperma Sunset, which was growing with white veins. All I changed was I added additional DPTA Iron to my micro mix, and no more white veined growth was seen. I believe @Zeus. also had some quite significant iron issues on his tank if memory serves.


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## dw1305 (22 Sep 2020)

Hi all, 





Geoffrey Rea said:


> Try not dosing it at all for several weeks, take weekly photos. It will take an age for iron deficiency to appear across the entire tank.........


I'd agree with @ceg4048 & @Geoffrey Rea on that. I've had long time periods (certainly months and possibly years) where I haven't added iron (FeEDTA) to the tanks, without the floating plants showing iron deficiency.

I add iron EDTA now on a <"slightly more regular basis now">, but purely because iron isn't mobile within the plant and after you have deficiency symptoms it takes a while for new leaves to grow (once iron becomes available again). Iron deficiency, in a floating plant, is the only deficiency I'm usually willing to diagnosis. 

You have a <"myriad of possibilities"> where older leaves are chlorotic and growth is compromised, but small, very pale, new leaves are strongly indicative that iron is <"Liebig's limiting nutrient">.

My guess is that nutrient deficiencies are much more likely to occur with carbon (C), nitrogen (N), potassium (K), phosphorus (P), magnesium (Mg) etc. (and probably in that order), purely because the plants need more of them.





Wookii said:


> I had what was diagnosed as an iron deficiency on the new growth of my Hygrophila Polysperma Sunset, which was growing with white veins. All I changed was I added additional DPTA Iron to my micro mix, and no more white veined growth was seen. I believe @Zeus. also had some quite significant iron issues on his tank if memory serves.


We have a number of threads where plants show <"iron deficiency">, often involving <"_Rotala rotundifolia"_>. 





Wookii said:


> Turning the question on its head though Geoff, what is the reason not to dose daily?


If I had an automatic doser, and was interested in optimal plant growth, I probably would dose daily, rather than scattering a pinch of FeEDTA in the tank when I notice the vial in the drawer.

If you aren't interested in optimal plant growth then I'm pretty sure it doesn't matter when you dose. If you use the Duckweed Index then you may find you don't dose anything for extended time periods.

cheers Darrel


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## Geoffrey Rea (22 Sep 2020)

Wookii said:


> Turning the question on its head though Geoff, what is the reason not to dose daily? What is the benefit of dosing alternate days instead



Couldn’t tell you, all paths seem to lead to Rome with EI and quite frankly I say try it, try as many different methods and report any discernible difference in your plants. Why is EI formatted with six days application with a seventh day of rest? What is this, Genesis?



Wookii said:


> but I had what was diagnosed as an iron deficiency on the new growth of my Hygrophila Polysperma Sunset, which was growing with white veins. All I changed was I added additional DPTA Iron to my micro mix, and no more white veined growth was seen.



Not to nit pick but that is plant specific, not tank wide. Different plant but... As Darrel has mentioned elsewhere with Rotala’s, they can be resistant to iron uptake due to adaptation from growing in specific habitat conditions.


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## Gulczi (24 Sep 2020)

So I will make a EI fert with seperate bottles for Macro and Micro but I will dose daily Macro and Micros instead of 3x week.
Will see what happens..


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## lilirose (24 Sep 2020)

I don't dose EI, but when I add iron at the same time as my weekly all-in-one, the water turns an ugly blackish colour. A couple of times I've dosed ferts, iron, and tannin tea on the same day and had the water turn black. Not "blackwater" tannin stained black, but straight up solid black, so that I could not see the fish or the plants. Attaching a photo as proof- you can barely see the bright blue Betta who is literally next to the glass, and you can see the reflection of my hands, the rest of the water is solid black- you can't see the back of the tank at all. I did not add anything unusual or in a larger dose than recommended.

Again I don't dose EI, but I thought that what you see in my pic is the reason for not dosing iron with the others.


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## Wookii (24 Sep 2020)

lilirose said:


> I don't dose EI, but when I add iron at the same time as my weekly all-in-one, the water turns an ugly blackish colour. A couple of times I've dosed ferts, iron, and tannin tea on the same day and had the water turn black. Not "blackwater" tannin stained black, but straight up solid black, so that I could not see the fish or the plants. Attaching a photo as proof- you can barely see the bright blue Betta who is literally next to the glass, and you can see the reflection of my hands, the rest of the water is solid black- you can't see the back of the tank at all. I did not add anything unusual or in a larger dose than recommended.
> 
> Again I don't dose EI, but I thought that what you see in my pic is the reason for not dosing iron with the others.



Wow, that is bad! I suspect there must be something else going on there - it was my understanding that the reaction between iron and phosphate produces white precipitate, not black? Does your AIO not contain iron already?


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## lilirose (24 Sep 2020)

I use EasyLife Profito in that particular tank (it's mid-tech, with easy plants and bio CO2). EasyLife don't list the full ingredients for Profito anywhere. Iron is mentioned in passing as an ingredient on their site, but they also recommend dosing EasyLife Ferro separately. Whether that is down to "please buy more EasyLife products for best results!"or not, I'm not sure - however, I dosed extra iron because I've a süßwassertang rope in the back of the tank which I wanted to grow more quickly, and I find süßwassertang grows faster in the presence of extra iron.

I bought into the whole EasyLife ecosystem last year, it works pretty well in low-tech tanks. But as I use up my stock, I will probably move to something a little more well-targeted for my various tanks, especially as I am setting up several that are high-tech. I've seen EasyLife precipitate out of the water when added to RO in a bucket, too, but I've never seen it precipitate in a tank, thankfully.


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## X3NiTH (24 Sep 2020)

lilirose said:


> A couple of times I've dosed ferts, iron, and tannin tea on the same day and had the water turn black. Not "blackwater" tannin stained black, but straight up solid black, so that I could not see the fish or the plants.



Easy Life Profito appears to be loosely chelated as it can precipitate when dosed depending on the pH, it appears metal rich, but maybe not in Iron as the company recommends to dose their other Iron product, but it does appear rich in other metals as Darrel suspected this from this post here.

When you dose a loosely chelated metal mixture into receiving water that will absolutely be out of pH range for the storage conditions in the bottle you are at least guaranteed some precipitation. If you dose this alongside another chelate and one as massive as Tannic Acid I would suspect the reaction would be pretty spectacular depending on the metal being chelated, in this case I suspect it’s the Zinc as it oxidises and turns black if dosed unchelated into neutral pH water. Whether the Zinc has oxidised or not before it’s chelated with the Tannic Acid it certainly does when it’s bound because it’s turned the Tannic Acid molecule opaque to light allowing you to see it, the effect will be temporary though (?hours/days) as the Tannins eventually flocculate and become too heavy to remain in suspension and drop out of the water column.


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## lilirose (24 Sep 2020)

Thanks @X3NiTH , I knew "adding these ferts with tannins gives a bad result" but I didn't know the reasons behind it, so I thank you very much for the detail, it's very valuable to me to understand what happened.

When my water turned solid black I first tried adding a HOB stuffed with a bag of activated charcoal for 24h, that did nothing besides upset the Betta. I took the HOB off, then waited four days before I got tired of not being able to see what was happening in the tank, and did another massive water change. Now I just don't add those three things on the same day- it seems to be fine if I dose Ferro on Monday, Profito on Tuesday, and tannins on Wednesday.


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## Wookii (24 Sep 2020)

lilirose said:


> Thanks @X3NiTH , I knew "adding these ferts with tannins gives a bad result" but I didn't know the reasons behind it, so I thank you very much for the detail, it's very valuable to me to understand what happened.
> 
> When my water turned solid black I first tried adding a HOB stuffed with a bag of activated charcoal for 24h, that did nothing besides upset the Betta. I took the HOB off, then waited four days before I got tired of not being able to see what was happening in the tank, and did another massive water change. Now I just don't add those three things on the same day- it seems to be fine if I dose Ferro on Monday, Profito on Tuesday, and tannins on Wednesday.



Does adding the tannins all in one go not cause a big and sudden pH drop? i would have thought you would be better adding some alder cones for gradual and natural release of tannins?


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## lilirose (24 Sep 2020)

Wookii said:


> Does adding the tannins all in one go not cause a big and sudden pH drop? i would have thought you would be better adding some alder cones for gradual and natural release of tannins?



What I was doing in my Betta tanks before this "disaster" was to have the amount of tannins fairly constant by adding some tea made from crushed Indian Almond leaf daily, rather than adding it once a week. Now I add it every third day or so- the Bettas seem to like it and not be bothered by any pH drop (which I have never actually measured TBH).

I don't like to use alder cones in the Betta tanks because they get stuck in the siphon when cleaning, but I use them frequently in my shrimp tanks.


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## Oldguy (24 Sep 2020)

lilirose said:


> tannin tea on the same day and had the water turn black.


You probably made ferric tannate which is dark blue/black. It was used to make ink, though I found it to lack opacity when I tried making some and lacked contrast on paper.

I make up my own macros ie pot nitrate and pot dihydrogen phosphate in separate stock bottles. MgSO4 crystals I add as a small fist full at water change. Tap water is moderately soft and contains little or no Mg and I cut with rain water, it therefore has very little in the way of nutrients, hence the Mg.

Iron is via EDTA and comes with a list of trace elements and is kept in a separate stock bottle.

Usually dose alternative days. At water change I double dose with macros and one glug of Fe EDTA & Trace solution. Never had any ppt. 

When going on holiday I 'front load' with  ferts.

I assume that if its in the water column the plants will take what they need. Its often a matter of balancing light and CO2 more than how/when you dose.

Keep watching your plants. (Not all plants require the same amount of light).


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## X3NiTH (25 Sep 2020)

Oldguy said:


> You probably made ferric tannate which is dark blue/black. It was used to make ink, though I found it to lack opacity when I tried making some and lacked contrast on paper.



Damn I totally forgot about Iron Gall Ink (Windsor&Newton Black Artist Ink) I’ve used loads of it in the past, Metal Tannates are used for their anti corrosion/fouling properties particularly Iron oxide for blueing steel.


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## lilirose (25 Sep 2020)

@Oldguy - That is an amazing coincidence of hobbies. I love this forum- after it happened I thought I would never know the details of exactly "why". I have learned so much from this thread!


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## ceg4048 (6 Oct 2020)

Wookii said:


> I've never been able to find an accurate explanation for this.
> 
> I understand the need to store concentrated micro and macro mixes separately to try and avoid the iron and phosphate reaction and resulting precipitation (though of course there are techniques for AIO solutions that we are all aware of), but when dosing EI, there will (or should) always be a prevailing levels of PO4 in the water column, so why does it make any difference if we dose micros and macros on alternate days, vs everyday at half the alternate day dose?
> 
> ...


The answer to this question is exactly as stated by sparkyweasel in post #5. Yes, it is true that Fe and PO4 reactions "can" occur in some tanks, especially if the water is hard (one will observe the precipitation of Iron Phosphate), however, you "can" get away with dosing both on the same day. There are too many variables to make specific instructions for each case, so EI provides simple guidelines to cover as many situations as possible. This does not mean that the principles should be interpreted as some kind of dogma. Always try to  remember that the EI dosing procedure was published years ago at a time when the whole world was paranoid of nutrients, so Barr came up with some simple procedures to help the uninitiated. 

Dose any way you wish, daily, alternate days, whatever. The day of rest is simply the result of arithmetic and convenience, since the concentration of nutrients will be sufficient, but, if you want to dose on that day then go for it, but it's unnecessary.

Hope this helps.

Cheers,


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