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  Topic Review (Newest First)
05-09-2013 09:36 AM
Jafooli Cheers I will try to get my CO2 working better, its stressful when I don't understand something 100% but as Zorfox mentioned about EI giving the plants a limited amount of nutrients, I guess in my mind plants used more nutrients than they actually do, but I will get back to my EI dosing and focus on CO2 and if I notice any deficiency signs i'll be back here lol. Thanks again.
05-09-2013 06:32 AM
plantbrain Fuss with CO2, dosing ferts is a very simple matter.
Do not make more work and heachache for yourself.
05-08-2013 10:27 PM
Jafooli Cheerz for explaining that all to me Zorfox, sorry if it feels like your repeating your self, just wanted to make sure that the lower end of EI is still sufficient enough for my tank as I am well planted, its good to know my plants wont be limited of nutrients I hope that to be the case once I get adding the K2SO4.

I have hopefully amended my CO2 issue as-well, which is on the DIY section, I have been keeping a close eye on my bubble count and my new mix is keeping it nice and stable at 2bps, I'm not sure how long it will take to see if its made a difference, not sure how quick algae dies off with correct CO2, but I will keep learning and gaining experience I hope from this forum
05-08-2013 07:25 PM
Zorfox The K2SO4 you received was probably exposed to moisture. It shouldn't hurt anything. Just keep it in a dry area.

EI is a non limiting way to dose nutrients. A limiting factor is something that limits the growth of our plants. If we add more fertilizers than the plants need, nutrients will never be the limiting factor. The good thing about the fertilizers we use is that marginal excess doesn't cause problems with fauna or algae. We would have to dose many times higher than the recommended ranges before we see problems. So essentially as long as we are providing the low end of that range up to 3-4 times the top end it's all good. As I said EI is not an exact method. It was never intended to be. This is one of the reasons it confuses so many people. Forget about calculating exact ranges, deciphering uptake ratios, worrying if a teaspoon weighs 10% more than it should etc. Just get the range of each nutrient near the target and then worry more about the difficult things such as getting CO2 levels where they should be.
05-08-2013 06:46 PM
Jafooli Just to add my K2SO4 arrived today some of it was clumped like a sugar cube, is this the texture of K2SO4?, I will be making my new batch tomorrow as my bottle now is near the end anyway, or I could just add 1/4 till I run out of my 500ml macro bottle.

Can I just ask as I was thinking, why would people dose higher in there tanks than needed, for example you said all the above measurements would work in my tank, Its strange how EI has such a big margin for error etc and you can dose little or lots more.

My tank has a lot of plants, so would my dose now compared to the larger doses still give me the same growth rates? I could not understand as when I put in my ppm of stuff and w/c etc, it always says 90% uptake to begin with, if I added 20ppm of stuff for example there is no way it would be 90% uptake, I will keep messing around with it and try to understand, I could not find no where which explains it properly.

Also a pic of my tank if it helps.

Attachment 139674

I will still stick with what we said regarding the measurments, but just kind of trying to figure how come there is such differences in measurements, and as I have so many plants I thought maybe my uptake would be more, so larger ppm per dose may improve my growth rates? or is even the lowest dose enough for all the plants?
05-07-2013 08:00 PM
Jafooli Thanks Zorfox I will just stick to what I dose now then and add the K2SO4.

I took a look at and it looks to confusing for me to understand I don't even know where to begin on there which is a shame as I enjoy learning all this, but hopefully you have put me in the right direction and as long as my plants are getting the food they need I'm happy.

Hopefully my potassium deficiency will be fixed and then I can keep an eye on my plants and see what they tell me next.

Thanks for your help, once again.
05-07-2013 07:40 PM
Zorfox You would have to be very excessive to harm your fish. Many people far exceed the levels I posted without any problems. As far as your mixture, I would just add the potassium to what you are currently using. No need to waste what you have. If you want to play around with projected nutrient levels try,, to see what they will be based on plant uptake, water changes, dosing etc. For me at least it was the aha moment when I saw it graphically, then it all made sense.
05-07-2013 07:13 PM
Jafooli Thanks Zorfox for your advice.

I guess I am over thinking it as I kind of like to understand everything 100% lol, that's why I try to follow everything I read or see, and the calculator was giving them measurements so I wanted to be sure on which one to follow before I make a new batch and find all my fish dead that was my main concern/worry

The reason EI daily confused me is because like you said, each dose of KH2PO4 will give me 0.60ppm so for the first dose I won't even be in the ppm range if that makes sense, and the time I get in the ppm ranges I will be removing 50% of the water.

So for me to understand this, as long as at the end of the week, my dosing is with in the ppm ranges, even if the first dose don't get me in range, it will still be giving the plants what they need as long as I reach the ppm ranges by the end of the week or come close, or even more.

Also just to add you said all the above dosing methods would work, is it possible that The Estimative Index calculations being the highest would harm/kill fish, or does EI have to be dosed really excessively to harm fish aka accident overdose etc.

I will probably make the batch you recommended or do what I'm doing now as I know my plants are happy apart from the potassium deficiency and then I'll just add the 18g K2SO4 like you said
05-07-2013 06:49 PM
Zorfox You seem to be over thinking it. I'm guilty of this myself most of the time. The basics of the system are to keep the nutrients around the levels listed previously (even higher is okay). It also is to simplify the dosing regime and provide more than enough room for error. So take KH2PO4 for example...

According to the calculator for EI daily add 2.149g to your 500ml container. Each 18ml dose will bring PO4 up to 0.60ppm. Dosing on alternating days (3x/week) will give a level of 1.8ppm. The range is 1-3ppm or even higher. That's within range. Even if you use EI weekly the dose will not be too much. You can use either. The theory is to provide excess and reset each week with large water changes. Just go with the daily dose and add more if the plants need it.
So to mix your Macro bottle add the following,
KH2PO4 approximately 3G
K2SO4 approximately 18G
MgSO4 add the dose recommended by the seller since we don't know which form they used. Remember you may have magnesium in your water as well.

Dose 18ml of this every other day. The reason the doses aren't exactly as the calculator listed, ie 2.149g for KH2PO4, are because EI is not an exact dosing regime. The doses listed will be fine for your needs. No need to calculate things to death. All of the amounts you listed will work.
05-07-2013 11:14 AM
Jafooli Just a update on this thread as I need some last advice please, as yesterday I purchased some K2SO4, so am now working out how much I will be needing to add to my 500ml solutuion at 18ml a dose 3x a week. The K2SO4 will be added to my Macro Solution. Sorry if this turns into a confusing/complicated essay but you can skip it all if you read my main question below and just answer that for me ( I also am not dosing KNO3 as you know but have used it below just for examples)

Anyway my MAIN question, on do I need to follow the grams for EI Daily or The Estimative Index, I have seen this question asked by some people on here and no one replied to them so am I right in saying EI daily would be you add KNO3 each day at the grams it provides "18ml a day in my scenario", and the The Estimative Index provides the grams for 2-4x week which I will be doing 3x 18ml. I know me and Zorfox spoke about it, and I think we talked about EI daily but I am getting massive gram differences between the two which in is putting me out of the PPM ranges, a good example is MGSO4.

Here is an example of what I mean:

My Measurements recommended from where I purchased and what I'm dosing now minus the KNO3

KNO3 - 4tsp = 29grams = 7.11ppm per dose, (21.33ppm week)
KH2PO4 - 1sp = 9grams = 2.51ppm per dose = (7.53ppm week) Way To Much?
MGSO4.7H2O - 6tsp = 31grams = 1.22ppm per dose (3.66ppm week) Way To Low?

The Estimative Index From Calculator Below:

KNO3 Nitrate 30g 7.50ppm each dose (22.5ppm week)
KH2PO4 Potassium Phosphate 4.6g 1.30ppm each dose (3.9ppm week)
MGSO4.7H20 Magnesium Sulphate 126g 5ppm each dose (15ppm week)

EI Daily From Calculator Below:

KNO3 Nitrate 13.044g 3.20ppm each dose (9.6ppm week)
KH2PO4 Potassium Phosphate 2.1g 0.60ppm each dose (1.8ppm week)
MGSO4.7H20 Magnesium Sulphate 50g 2ppm each dose (6ppm week)

So EI daily would hardly get me in the ppm ranges at 3x a week, and The Estimative Index would get me in the ranges from the first dose, and keep me in the ranges roughly all week.

For some reason my starter kit has low MGSO4 even compared to EI daily, and MGSO4.7H2O The Estimative Index recommends 126g, I am only using 31g, so this what I mean by its quite scary for someone who is inexperienced, and I know I am making this more complicated, way more complicated, but do I go with EI daily or The Estimative Index.

If my Macro mix sounded right I could of just added 1/4 tsp K2SO4 to my tank 3x a week but I want my macro's all together in a solution, I guess this is why its become a little complicated and the way I have presented all this.

Also to try and answer my own question about the K2SO4, plantbrain recommended K2SO4 at 1/4tsp 3x a week, that's 7.98ppm a dose, (23ppm week) and my 18ml would be 41g into 500ml, 18ml 3x a week gives me 22.5ppm. So all in all am I right in saying The Estimative Index is correct for 3x a week.

PPM Ranges:

KNO3 - 5ppm-33ppm
KH2PO4 - 1-3ppm
MGSO4 - 5-11ppm
K2SO4 - 9-33ppm

My Tank

90 litres - 20G

Think there correct from the "Yet Another Nutrient Calculator"

Also thanks jfynyson thanks for your input, I only really needed to know the estimated teaspoon weight just to see how much grams I was dosing so could tell my ppm each dose, the link zorfox provided is quite close with teaspoon weights but as I learned on my scales each teaspoon can fluctuate a gram or two or my scales are busted lol.
05-02-2013 08:18 PM
jfynyson ok so the reply post messed up my formatting. PM me and I can send you a spreadsheet.
05-02-2013 08:17 PM
jfynyson As far as the conversions you list. Technically speaking each salt will weigh different based on it's bulk density. Example a teaspoon of lead will weigh more than a teaspoon of feathers.

So, to take care of this issue I normalized it. I said in general if a solid oz weighs 28.35g and then convert that into tbls & tsp. See below:

g / 1 tblsg / 1 tsp14.184.731 solid oz (28.35g) is equivalent to 2 tablespoons (or 1 tablespoon is 14.18g)1 solid oz (28.35g) is equivalent to 6 teaspoons (or 1 teaspoon is 4.73g)1 teaspoon is 1/3 of a tablespoon or 3 teaspoons per tablespoon

So therefore according to EI dosing I converted the following:
100-125gal Dose 3x per WeekWt (tsp)Wt (g)KNO31.507.10KH2PO40.502.37K2SO40.502.37Plantex CSM+B0.502.37

Keep in mind a solid oz is not a fluid oz which would have to take into account the density or specific gravity.
05-02-2013 07:35 PM
Originally Posted by Zorfox View Post
Yes it's fine 3 x 7.5 = 22.5ppm in a week. The range is 10-30ppm. See the wiggle room? lol
I was going to create a similar thread but this just about cleared up the last of my questions. Thanks for the info and thanks to the original poster for starting this thread!
05-02-2013 04:08 PM
Jafooli Thanks Zorfox

I will use my measuring scale when I make my new Macro Mix which does grams.

I just wanted to know the teaspoon weights to get a idea of how much I am currently dosing as the shop I purchased from just told me to add 1tsp then 4tsp etc.

When I make my new Macro Mix following the calculator I will be able to see how much more/less I am adding which will be interesting.

Also thanks to the calculator I can see where I am in the weekly ppm ranges. I guess it don't matter if I'm on the low end or high end. but hopefully the calculator recommended ppm's will put me in the right direction.

Thanks for all your help.
05-02-2013 01:49 PM
Originally Posted by Jafooli View Post
I was actually wondering where Zorfox got this information and how I can find it:

Potassium Nitrate (KNO3) 1 teaspoon = 5,200mg
Potassium Phosphate (KH2PO4) 1 teaspoon = 5,800mg
Magnesium Sulfate (MgSO4.7H2O) 1 teaspoon = 5,100mg
It's from one of the master files for that calculator,

Remember, the weights for teaspoon can vary quite a lot. I think it's close enough for EI dosing though.
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