• You are viewing the forum as a Guest, please login (you can use your Facebook, Twitter, Google or Microsoft account to login) or register using this link: Log in or Sign Up

EI DOSING USING DRY SALTS

Haha yes definetly. I have some powders which have arrived but it looks like I'm going to be getting onto them quicker than I first thought at that dosage
 
I am just organising my purchase of powders. It appears they are out of stock on Potassium and Magnesium so will have to wait on those

A few questions

1) What does 13% EDTA Chelated mean when purchasing Iron, there seems to be 13 or 8% variations?
2) Is it worth dropping the Iron (Fe) and just dosing CSM+B Trace elements which contain Iron + all the other goodies? (See Below)

CSM+B.JPG


3)How long does the powder last? I was looking at buying 12 months worth of powder then making mixes each month with required amount of solution? Is it worth making a stronger solution to last say 3 months or would the powder start to degrade in the solution?
4)Can you mix Powders to form a Macro Solution or will some powders react if mixed or dosed at the same time?
5)I was looking at dosing from 1 hour before CO2 turns on up until 1 hour before light ramps up to full power (6am - 11am). I have read suggestions of dosing all in one go at the start of the day but my theory is that a gentle drip feed would be better for plants and the fish? As I have an Auto-Doser is there any downside to spreading out the dosing?
6)I understand that with an increase in nutrients I need to ensure they have enough light and CO2. Using a PH probe I am getting a PH of 7.08 before lights or CO2 turns on, this then continues to drop to 6.72PH once the CO2 is turned on but lights are off. Once lights go on I achieve the following readings
  • 10% Light - 1 Hour After Switch On - PH 6.60
  • 30% Light - 2 Hours After Switch On - PH 6.52
  • 50% Light - 3 Hours After Switch On - PH 6.48 (Infrequent Small Bubbles/Pearling Visible from large Anubias Leaf)
  • 50% Light - 6 Hours After Switch On - PH 6.40
Is this too much of a PH swing or not enough? I was expecting the PH to rise once the light switches on as the plants consume the CO2?​
7)Is there a maximum concentration of powders I can use for 1000ml of RODI water? For example if I doubled Nitrogen from 21.6g to 43.2g could I just use half as much solution threfore giving me longer between refills of my dosing container?
Potassium+Magnesium.JPG


Below are my calculations for my 270 litre tank. Based on a mix of 1000ml of RODI water I would dissolve the red numbers into that solution and then dose 36ml per day via the Autodoser during the photo period?

Can someone confirm the numbers for me just so I can make sure this is correct?

Table.JPG
 
Is there a maximum concentration of powders I can use for 1000ml of RODI water?
Yes. Each compound has limited solubility.
Can you mix Powders to form a Macro Solution or will some powders react if mixed or dosed at the same time?
Don't mix it. Par example, phosphates readily form insoluble compounds with everything except sodium and potassium. Calcium forms insoluble (poorly soluble) compounds with everything except nitrate and chloride.
Dosing at the same time: Mostly safe. Still better dosing separately. Most sensitive are phosphates and all compounds containing iron.
 
Hi all,
Don't mix it. Par example, phosphates readily form insoluble compounds with everything except sodium and potassium. Calcium forms insoluble (poorly soluble) compounds with everything except nitrate and chloride.
Have a look a <"the solubility rules chart">.

If you download the <"Fert Calculator V1.8 - New version out! Check Note first/last post!"> it will tell you when you've exceeded the solubility limits for your "all in one mix".
Yes. Each compound has limited solubility.
You can find the "solubility limits" value for each compound on Wikipedia, this is the page for <"magnesium sulphate"> (MgSO4) and for "Epsom Salts" you need the value for the "heptahydrate", Mg SO4.7H2O of (a theoretical) 113 g/100 mL (at 20 °C).

You also need to take the <"common ion"> effect into account, this means that the least soluble salt will come out of solution first, and in practice somewhere well before you get anywhere near the theoretical limit.

cheers Darrel
 
1) What does 13% EDTA Chelated mean when purchasing Iron, there seems to be 13 or 8% variations?
It is the iron content in the mix. I would go for 11% or 13%. Avoid anything lower than 10% specially if you are preparing All-in-one solutions. The higher content of chelating agents in lower % Fe variations will tend to increase the PH of your solution, which you don't want since it can cause precipitations. If you test the PH of commercial fertilizers with chelated micros you will notice that the PH is around 2 or 3. This is exactly to prevent what I described above and to keep the solution stable.
2) Is it worth dropping the Iron (Fe) and just dosing CSM+B Trace elements which contain Iron + all the other goodies? (See Below)
That's the easy way to go and should work. Only issue with CSM+B is that from batch to batch the proportions of each individual salts can varie greatly. Now some people have use it successfully, so that's that, but I prefer mixing each element independently. It will obviously cost you more, but also will last you much longer.
3)How long does the powder last? I was looking at buying 12 months worth of powder then making mixes each month with required amount of solution? Is it worth making a stronger solution to last say 3 months or would the powder start to degrade in the solution?
Powders can be kept for many years if kept in sealed containers with least humidity possible. Don't prepare solutions which are too concentrated. This is DIY fert, not industrial, hence we have limited ways to prevent mold formation and other bacterial proliferation which spoil your fert mix. Mixes that last 1 to 2 months max is advisable.
Can you mix Powders to form a Macro Solution or will some powders react if mixed or dosed at the same time?
Better to keep salt powders separated.
5)I was looking at dosing from 1 hour before CO2 turns on up until 1 hour before light ramps up to full power (6am - 11am). I have read suggestions of dosing all in one go at the start of the day but my theory is that a gentle drip feed would be better for plants and the fish? As I have an Auto-Doser is there any downside to spreading out the dosing?
Everyone will have a say on this, so I'll just share what I do. I dose my micros after Co2 has been on for a good hour and half and a good half hour before lights are on. This allows the water to acidify which makes the nutrients in general more available to plants. Also, in my opinion it's also best to dose micro nutrients before lights are on because chelated salts are photosensitive and can degrade with light. If I was doing macros daily I would be less concerned and anyway I am front loading all my macros so that's that.
6)I understand that with an increase in nutrients I need to ensure they have enough light and CO2. Using a PH probe I am getting a PH of 7.08 before lights or CO2 turns on, this then continues to drop to 6.72PH once the CO2 is turned on but lights are off. Once lights go on I achieve the following readings
  • 10% Light - 1 Hour After Switch On - PH 6.60
  • 30% Light - 2 Hours After Switch On - PH 6.52
  • 50% Light - 3 Hours After Switch On - PH 6.48 (Infrequent Small Bubbles/Pearling Visible from large Anubias Leaf)
  • 50% Light - 6 Hours After Switch On - PH 6.40
Is this too much of a PH swing or not enough? I was expecting the PH to rise once the light switches on as the plants consume the CO2?
Not much to be honest, it's just a 0.6PH drop. In my case I have a 1.4PH drop.
Your PH probably rose a bit but because you took readings every hour you didn't see that increase happen. Also your light intensity progression is very slow. You go from 10% to 50% in 6 hours which allows Co2 to build up without being consumed too fast by plants.
7)Is there a maximum concentration of powders I can use for 1000ml of RODI water? For example if I doubled Nitrogen from 21.6g to 43.2g could I just use half as much solution threfore giving me longer between refills of my dosing container?
Yes. As commented by both @dw1305 and @_Maq_ all salts have solubility limits. This said, when using the IFC Calculator you will be informed of the solubility of each compound you are using and if you are reaching its solubility limit. The calculator was also built with the premise that because you are mixing multiple salts together, individual solubility is also impacted, therefore the calculator is by default set to 75% of the actual solubility of the salts. This gives you some margin of error.
Can someone confirm the numbers for me just so I can make sure this is correct?
Check the IFC calculator which will confirm (or not 😉) your numbers.

edit: grammar/typos
 
Last edited:
Still don't know how people manage to not getting iron deficiency in hard water with EDTA CSM+B, maybe they deliver iron from the soil ?
 
Still don't know how people manage to not getting iron deficiency in hard water with EDTA CSM+B, maybe they deliver iron from the soil ?
I don’t think all hard waters are equal. For example Hard Water in Doncaster is a different mineral content makeup to hard water in Cambridge. Doncaster has plenty of magnesium in its hard water, Cambridge has less. I’m guessing it will be lots of these differences, maybe say different PH etc that will cause iron issues or not.
 
I believe it's not Mg/Ca content which makes iron dosing difficult, rather bicarbonates (alkalinity). And when dosing EI or similar it's phosphates which react with iron forming insoluble salts.
that makes sense, as it appears in my case a lower KH is what matters (makes a difference to the plant health), less so with GH.

Sorry for my lack of understanding here, but I generally just relate the alkalinity to KH, as in dKh. Do you know if on a water report this would also be referred to as “Alkalinity (as calcium carbonate)” and measured in “mg/l”? Or is this a different measurement to KH? Thank you
 
Last edited:
Thank you, so you are referring to ANC when you say Alkalinity, and it is this ANC that I measure with a hobby’s kit as dKH, and it measures the ability of the water to neutralise acid (and change PH), hence why we sometimes call it a buffer ability. Your excellent article states that this is rarely used in UK water processing plants, hence why I will struggle to find it on the water report. This is a shame, as I was hoping to understand why in theory “aquarium gardens” who everyone states has liquid rock water, does not get iron issues, whilst people in my area KH 8-9 do get the iron issues. But I will not be able to get this information from the water reports, as they do not measure ANC (or is this irrelevant, as that is more to do with bicarbonates). I was simply interested 😀

I see your section on bicarbonates mentions that this causes the iron issue. So in my tank, I could have lowered my KH with RO water (50% to reduce it from 8 to 4 Dkh) and see improvements in my plants (which I have 😀), but perhaps could still get iron issues due to excessive bicarbonates that are still present in the water?

Thank you
 
Last edited:
still get iron issues due to excessive bicarbonates
My alkalinity is usually close to zero. Water is soft, acidic, and I don't have to use any chelates to dose micros. In other words, if iron deficiency appears, I add ferric chloride (FeCl3) and problem solved.
If you inject CO2, you may like to have some alkalinity, about 1 °dKH, not to push your pH too low.
 
This is a shame, as I was hoping to understand why in theory “aquarium gardens” who everyone states has liquid rock water, does not get iron issues, whilst people in my area KH 8-9 do get the iron issues.
I think the iron issue is not directly related to the KH, but rather to the higher pH, a consequence of high KH. It is difficult to keep iron in solution at high pH. If I am not mistaken Aquarium Gardens uses CO2 injection, as well as @George Farmer, who also uses hard hard water. They need to inject a bit more CO2 and there are a few plants that still do not do well in hard water. The CO2 injection lowers the pH.
I solved my iron issues in my 12 dKH tanks by dosing the iron in the morning together with a dose of club soda (CO2 source, made with SodaStream). The transient drop in the pH seems to be sufficient for the plants to take up the required iron dose. Also, I use Fe-DTPA which does better at higher pH.
 
I think the iron issue is not directly related to the KH, but rather to the higher pH, a consequence of high KH.
It is difficult to separate the effects of both as they are inherently tied to each other. Still, I believe both have their negative effects. There are some plant species which are considered quite sensitive even by CO2 users, while I - not using CO2, but keeping alkalinity close to zero - see no difficulty in keeping these species. And I don't have to use any chelates.
 
I think the iron issue is not directly related to the KH, but rather to the higher pH, a consequence of high KH. It is difficult to keep iron in solution at high pH. If I am not mistaken Aquarium Gardens uses CO2 injection, as well as @George Farmer, who also uses hard hard water. They need to inject a bit more CO2 and there are a few plants that still do not do well in hard water. The CO2 injection lowers the pH.
I solved my iron issues in my 12 dKH tanks by dosing the iron in the morning together with a dose of club soda (CO2 source, made with SodaStream). The transient drop in the pH seems to be sufficient for the plants to take up the required iron dose. Also, I use Fe-DTPA which does better at higher pH.
Thank you for your input. Very interesting, I did wonder if this (PH) was also playing a factor, especially after reading the hard water article by Maq. This makes sense, as both the area I live in and Cambridge (aquarium gardens) have hard water (although I don’t know their KH), but I assume cambridge will have a high KH. From the water reports I can see that my PH is higher than Cambridge, and my actual degassed water has an even higher PH of around 8.0 - 8.1. So the mixture of my tap water having both a high PH and KH causes / plays a part in my iron deficiency. hence why I have to dose with a mixture of chelated irons (DTPA & EDDHA) just before lights on after co2 is to maximum level (I have to put co2 on 5 hrs before lights on, and inject at a high rate).

Over the last couple of weeks I have moved over to 50% RO, 50% Tap Water. I can see the reduction in KH has really transformed what I can grow (possible to grow rotala now), but I have yet to see if I can reduce Iron dosing, as the PH does not reduce as much with the 50 % RO, as say the KH does (KH has reduced from 8 to 4, GH 20 to 10)

Thank you and Maq for assisting me in better understanding the mechanics behind this 😀
 
Last edited:
Cambridge dKH is 14+. Don't trust the water report's lies about pH - the Cambridge water report claims pH of 7.4 which isn't possible for atmospheric gas and pressure equilibrated carbonate buffered water with such a high dKH.

@Aquarium Gardens injects what looks to me to be pretty aggressive levels of CO2 judging by the colour of their drop checkers - they have amazing looking tanks. I don't know what they do for iron chelation, but I'd be interested to find out.
 
the PH does not reduce as much with the 50 % RO, as say the KH does (KH has reduced from 8 to 4, GH 20 to 10)
Reducing the KH to half should in theory reduce the pH by ~0.2 if you have the same CO2 levels, so a smaller pH reduction relative to KH is normal. The connection between the KH and pH is on a logarithmic scale.
 
Cambridge dKH is 14+. Don't trust the water report's lies about pH - the Cambridge water report claims pH of 7.4 which isn't possible for atmospheric gas and pressure equilibrated carbonate buffered water with such a high dKH.

@Aquarium Gardens injects what looks to me to be pretty aggressive levels of CO2 judging by the colour of their drop checkers - they have amazing looking tanks. I don't know what they do for iron chelation, but I'd be interested to find out.
Wow that’s a high KH.
I have had a conversation with them about iron. From speaking to them, they mainly use APT complete (and dose as per instructions),as well as root tabs for fertilisation. They do not add a separate iron fertiliser, and they think iron deficiency simply arises from EI dosing (EI dosing causing high levels of nutrients blocking iron). I can understand why they may think this, as they do not get iron deficiency.They do appear to regularly replace parts of the substrate, when they do replant stems, perhaps this provides the iron??

Having tried APT complete myself, I know that even though it includes different chelates (I have asked the amounts from 2hr, but they will not disclose, only that it includes DTPA & EDDHA) , and there is not enough chelates in it for my water. I have tried both APT Complete & APT EI at Full EI Levels, and there are not sufficient levels of chelated iron. . Only when I dose iron chelates on a separate day, can I stop iron deficiency.
 
Last edited:
Reducing the KH to half should in theory reduce the pH by ~0.2 if you have the same CO2 levels, so a smaller pH reduction relative to KH is normal. The connection between the KH and pH is on a logarithmic scale.
That’s sounds about right, my PH has only dropped a small amount, perhaps 0.2 😀 , as can be seen by the PH drop after co2 injection, as it is now 0.2 PH Lower than it used to be.
 
Last edited:
Back
Top