How do I calculate how much I'll need?

[Progen]

I've been using Seachem's recommendation of 5ml per 60 gallons for the past two months and with my fairly high light and CO2 injection rate, that was obviously not enough which was why many of my plants were sending out transparent and sickly looking new leaves so I upped the dosage by 3x and my plants have been looking so much better ever since. I also noticed on the Barr Report that 6x Seachem's recommended dosage was suggested for someone's tank which was double mine so I reckon I've done right then.

Anyway, I feel that my rooted plants can still look even better if I added a bit more iron to the water and now that I've added less baking soda per water change to get the pH to be slightly below neutral, I should be able to use EDTA iron, right? How do I calculate how much I'll need and what kind of ppms will I be introducing?

I drop by a baking supplies shop every now and then so I know where to get ascorbic acid. I read that it will convert the EDTA's ferric iron to a ferrous form but how do I know what kind of ratio to start with?

Any help will receive my eternal gratitude.

 

[Progen]

I came across this table from another website showing a micronutrient product from the same company. The copper value seems to be extremely high compared to Seachem Flourish's 0.0001%. I have some Amanos and Indian Whisker shrimps inside. Will this level be toxic to them?

1. Boron (as B): 0.50%
2. Cobalt (as Co): 0.05%
3. Copper (as Cu): 1.50%
4. Iron (as Fe): 4.00%
5. Magnesium (as Mg): 5.43%
6. Manganese (as Mn): 4.00%
7. Molybdenum (as Mo): 0.10%
8. Zinc (as Zn): 1.50%
9. Practical pH Stability Range: 4 - 9 (in aqueous solution)

 

[Ed.Junior]

Fe doses are something very "personal". You will get all sorts of opinions.

The "usual" dose is around 0,2 ppm weekly. I have seen people getting great results with less (0,1) and way more (1,0).

You have to try it for yourself.

Sent from my SM-G920F using Tapatalk

 

[xim]

I drop by a baking supplies shop every now and then so I know where to get ascorbic acid. I read that it will convert the EDTA's ferric iron to a ferrous form but how do I know what kind of ratio to start with?

You can get an idea about the amount of ascorbic acid to use here. But I use 1 gram per 500 ml personally.
http://www.theplantedtank.co.uk/allinone.htm

Ascorbic acid can reduce iron, but I found this property quite useless because the iron will be oxidised back to ferrous almost immediately when you pour it into the tank. It's unlike gluconate which is both a reducer and a ligand, thus it can "protect" the iron for a while. Ascorbic acid's main purpose here is to lower the pH of the solution.

Oh, for anyone wants to "really" replicate TPN+, the table in the link won't get you there. TPN has a unique character about having lower Zn than Cu, apart from using HEEDTA and DTPA (the latter is not so unique nowadays, though).

I came across this table from another website showing a micronutrient product from the same company. The copper value seems to be extremely high compared to Seachem Flourish's 0.0001%. I have some Amanos and Indian Whisker shrimps inside. Will this level be toxic to them?

1. Boron (as B): 0.50%
2. Cobalt (as Co): 0.05%
3. Copper (as Cu): 1.50%
4. Iron (as Fe): 4.00%
5. Magnesium (as Mg): 5.43%
6. Manganese (as Mn): 4.00%
7. Molybdenum (as Mo): 0.10%
8. Zinc (as Zn): 1.50%
9. Practical pH Stability Range: 4 - 9 (in aqueous solution)

This looks like Miller's Microplex, apart from maganesium that is a bit different.

The problem is not in the number. Seachem percentage is very low because it's mixed with water while the Microplex is dry powder. You can dilute it to any percentage you want.

But Microplex has a problem about copper ratio to other nutrients. When you dilute it to get a safe level regarding copper. Other nutrients will be too low.

 

[xim]

Fe doses are something very "personal". You will get all sorts of opinions.

The "usual" dose is around 0,2 ppm weekly. I have seen people getting great results with less (0,1) and way more (1,0).

You have to try it for yourself.

Sent from my SM-G920F using Tapatalk

This is, I think, from the quality of the chelators being used. Brands with Fe-Gluconate will generally have very high Fe ratio compared to brands that use EDTA or DTPA. I suspect it's to compensate for the shorter life in the water column.

Further more, the quality is not the same among the same class of chelator. I've found Fe-DTPA from a brand precipitated immediately when I added KH2PO4 into the mix, so it couldn't be used to make an all-in-one fert, while Fe-DTPA from another brand (AKZO NOBEL Dissolvine® D-FE-11) worked really well. If you look at a catalogue of a chemical manufacturer, you can see various sub-categories of chelators with various properties for specific uses.

 

[Progen]

But Microplex has a problem about copper ratio to other nutrients. When you dilute it to get a safe level regarding copper. Other nutrients will be too low.

Yeah, that's the problem. I tried calculating a safe dilution ratio based on Seachem's Flourish and it's kind of like back to square one with me having to buy some form of iron separately.

 

[Progen]

Here are some caution Copper levels to be aware of:

Dangerous level of copper for shrimps is 0.03 mg per litre.
Dangerous level of copper for algae and bacteria is 0.08 mg per litre.
Dangerous level of copper for some fish, snails and plants is 0.10 mg per litre.

Found this online.

Now I'm one of those guys who's not having a cushy job today because I didn't study hard in school but this is what I've worked out.

In the figures I posted of that trace mix, it contains 1.5% copper so 1 gram of that mix will then be :-

1.5/100*1000 which will give me 15mg of copper per gram of that trace mix.

Assuming a round figure of 200 litres as the volume of water in my 4'er, 1 gram will result in :-

15/200 which is 0.075 which is still 2.5x the lethal dose.

Am I right?

 

[xim]

Ascorbic acid can reduce iron, but I found this property quite useless because the iron will be oxidised back to ferrous almost immediately when you pour it into the tank.

Correction: ferric

 

[xim]

Found this online.

Now I'm one of those guys who's not having a cushy job today because I didn't study hard in school but this is what I've worked out.

In the figures I posted of that trace mix, it contains 1.5% copper so 1 gram of that mix will then be :-

1.5/100*1000 which will give me 15mg of copper per gram of that trace mix.

Assuming a round figure of 200 litres as the volume of water in my 4'er, 1 gram will result in :-

15/200 which is 0.075 which is still 2.5x the lethal dose.

Am I right?

Yes. But you have to factor in the accumulation as well. That is if your weekly water change is 50%. The highest theoretical amount of accumulation will be 2x. By this, the safe dose is 0.03/2 or 0.015 PPM a week or about 0.002 PPM a day.

However, those safety levels are based on free Cu in the water column. Chelated Cu is less toxic. So you can see using some brand of micros at EI level can result in a level exceeds the safety levels but there is no fish or shrimp death. But I set my own limit at 0.002 PPM of Cu a day anyway.

 

[Progen]

Thanks for pointing out the accumulation factor too. I've decided it's not worth the risk because at that strength, that few hundred grams will still be around after I'm dead but I've gone ahead with the EDTA iron purchase.