How long iron gluconate "live" in tank

[borman]

Friends,
Have some problems.
Some time ago i purchase iron gluconate (powder). Before that I use DIY EDTA Fe (based on Fe2So4*7H20)
I dose about 0,1 mg/ml day and plants seems to be quite ok. Also my Jbl fe test always show me about .3-.4

But after few days since I start dosing same ammount of gluconate I stated that some of my plants (rotala sp Green and H.Cuba) start shows the chlorosis signs.
I start dosing 0.2 at morning but when I do test at evening - its shows 0. I add 0.3 but it shows 0
May be the reason that gluconate rapidly decomposes and its not availible to plants. Cause I add it at 8 o`clock but light start at 10 o`clock and only 2 of my 4 t5 lams.
How long gluconate can "live" in water?

Thansk for any advice

 

[Tom Barr]

I'd say not long, you can dose more etc to make up for that, or more frequently.

I'd say it's similar to AA's and Citrates etc:

I use This+ DTPA and ETDA all together, I may even add a little of the EDDHA in, but not much.


Regards,
Tom Barr

 

[borman]

Thanks Tom
But in this case, what sense to add gluc at all. If it lives so small time ?
Actually i take this powder and simply add ro water. Also PH in my tank is about 5.0-5.9. May be i need to add something to stabilize solution. May be store it in frige ? Cause i cann not dose it more often (i go to work when light is still off, and return when its only 1 hour before its off )

 

[Tom Barr]

Well, I think a lot is wasted basically, but since the amount needed is small for plants, and the weaker ligand is more bioavailable, it's still worthwhile.
Folks have used Fe Gluconate for decades now since Seachem started adding it to their line up.

Seems to work well in softer water.
That's the practical side.

Regards,
Tom Barr

 

[borman]

I use This+ DTPA and ETDA all together, I may even add a little of the EDDHA in, but not much.

Tom is that mean that you add EDTA chelator (salt) to Gluconate solution or that you use Fer gluconate together with FeEDTA (or DTPA)
If yes - what ammount of chelator you add to solution?
Also did you add some acid to solution (for ex ascorbic)? Cause in me FeEDTA solution for example i add 1,44g of Fe2So4 +2.16 EDTA salt and 0.07g of ascorbic acid+100g RO water.

But the main problem is chlorosis. What to do bes now - increase amount of gluconate or add simultaneously EDTA FEW?

 

[Philosophos]

Wow... I had thought gluconate was kind of short lived but I hadn't realized that it was this brief.

I can see the possible advantage of spiking something easily available and short lived though; aquasoil's NH4 does things for plants that are incomparable with NO3 once the substrate cycles. It'll be a nice pairing with CSM+B's EDTA for aquasoil/low pH tanks.

I take it EDDHA is some pretty tough stuff for plants to break down? The price doesn't seem much off other chelates.

 

[jonny_ftm]

Plants can get the iron from the chelate directly, they don't need iron to be separated. The fact it resists to PH doesn't mean plants will have a tougher time to get it. In calcareous soils, EDDHA showed to be a very good iron supplier, so plants don't seem to bother

Gluconate could be a good alternative for a low maintenance tank with few WC. Gluconate is rapidely bioavailable while other chelates will take tens of years to degrade. Accumulation of chelates in soil can decrease its fertility. Also, I'm not sure if fish likes it in the long run at high concentrations.

Many unknown questions. If you use 50% WC, DTPA or even EDTA can be enough. Otherwise, DTPA is a good alternative, EDDHA for really calcareous conditions and gluconate as the "Bio" way!

 

[Tom Barr]

Tom is that mean that you add EDTA chelator (salt) to Gluconate solution or that you use Fer gluconate together with FeEDTA (or DTPA)
If yes - what ammount of chelator you add to solution?
Also did you add some acid to solution (for ex ascorbic)? Cause in me FeEDTA solution for example i add 1,44g of Fe2So4 +2.16 EDTA salt and 0.07g of ascorbic acid+100g RO water.

But the main problem is chlorosis. What to do bes now - increase amount of gluconate or add simultaneously EDTA FEW?

No, I used them already combined with Fe.

So it's Fe gluconate and ETDA Fe, and DTPA Fe etc.........already done.

I know many used to make their own using ETDA and what not.........but it's less hassle and simpler to simply buy what we need if it's avialble commercially .........which it is in the USA.

Regards,
Tom Barr

 

[Tom Barr]

Wow... I had thought gluconate was kind of short lived but I hadn't realized that it was this brief.

I can see the possible advantage of spiking something easily available and short lived though; aquasoil's NH4 does things for plants that are incomparable with NO3 once the substrate cycles. It'll be a nice pairing with CSM+B's EDTA for aquasoil/low pH tanks.

I take it EDDHA is some pretty tough stuff for plants to break down? The price doesn't seem much off other chelates.

Well, I and Roger Miller speculated long ago that a lot of the Fe never makes it to the plant.
I think it's still a stronger bond than say the citrates and amnio acids.

Sort of a midway range between the graph above. Unfortunately, I have no such graph for gluconate, but it can be estimated based on the bond's strength relative to these others.
There maybe some info in the mdeical uptake of Fe in vitamins etc in the research, I'm not sure.

Gluconates, citrates and amnio acids are used in those products.

As far as tough for a plant to break a bond, this is not true in the context of a whole plant's demand for Fe and energy used to acquire Fe.
It represents a very small % of energy of the entire plant. The main thing is really one of availability and consistency with Fe.

Good consistent non limiting Fe.
I do not think it's a bad idea to use a mix of different Cehaltors/ligands, but if you have a KH of 10-15, you better be using a lot more DTPA Fe relative to ETDA Fe.
If the water is softer, then perhaps ETDA and DTPA mix or gluconates etc.

NH4 vs NO3 would give the largest difference if there where any as far as energy difference.
Fe is "wayyyy down the line" comparatively.

There might be selectivity and preference by plants, I just like short term, medium term and longer chelators keeping things in solution, just covers all the possible outcomes, different plant species(300-400 we keep etc), etc.
This is a better hedge if you where going to guess. We are not going to be able to wait for any " real test" from research here.
So a management approach that addressed all the needs seems wise.

No BS about this "being a better product than that one" etc.
Then twisting the info to suit, like is often done with light and plant bulbs.

We do not know, but if, we where to come up with a good plan, this seems like a doesy.

Regards,
Tom barr

 

[Tom Barr]

Plants can get the iron from the chelate directly, they don't need iron to be separated. The fact it resists to PH doesn't mean plants will have a tougher time to get it. In calcareous soils, EDDHA showed to be a very good iron supplier, so plants don't seem to bother

Gluconate could be a good alternative for a low maintenance tank with few WC. Gluconate is rapidely bioavailable while other chelates will take tens of years to degrade. Accumulation of chelates in soil can decrease its fertility. Also, I'm not sure if fish likes it in the long run at high concentrations.

Many unknown questions. If you use 50% WC, DTPA or even EDTA can be enough. Otherwise, DTPA is a good alternative, EDDHA for really calcareous conditions and gluconate as the "Bio" way!

Yes, I do like the fact that Gluconate is easily degraded. I believe your thought is good thinking on the "organic" aspect. I know the ETDA/DTPA/EDDHA salts can persist and rechelate according to some litrature and ecotoxicology.
I hold the same view with the citrates and amnio acid ligands. These ligands are used for vitamins for humans.
Having said that, I see little evidence of long term effects in non CO2 planted tanks that have no water changes over 1-2 years time frames that are dosed with ETDA or DTPA.

But citrate and AA's are take up by the plants directly(glycine for example is often used and is better than adding NH4 for amnio acid synthesis, it's already made) and you get 100% of the product added being used by plants that way.
As you can see however, the bond is weak and has a low pH range also.

So this makes a good foliar spray in fetigation systems, perhaps a spike in a soft water aquarium etc.
Similarly, we could say the same about gluconates.

The persistent chelates can also detoxify metals present in soils and water.
So their benefit/detriment can go either way.

Persistence for DTPA is in this paper:

http://www.chelates-oilfield.com/NR/rdonlyres/81D99688-3A21-4124-9506-CFFE25A48C34/1339/TL241.pdf

So it does not last forever, few things do.

Regards,
Tom Barr

 

[Philosophos]

Okay, so the whole thing is more of a shotgun approach for the usual issue of serious research funding. I understand completely.

What I need to work on then is my understanding of how chelates interact with nutrients and uptake.

Thanks for the clarification, both of you.

 

[jonny_ftm]

Thank you Tom for these clarifications. I never thought that biodegradation of DTPA was that fast. One thing the paper doesn't adress is the accumulation of DTPA in the sediment, where light can't diffuse. Their graph shows well that DTPA will last for years in the dark. What I know is that DTPA can be pointed as one cause of soil infertility if too much used/accumulated. And, seeing their graph, it seems that DTPA will for sure accumulate in soil. Add to this, the paper is sponsored by Dissolvine ad-ons, so a chelate producer...

Now, if based on your expierience, the use of DTPA in non CO2 tanks with so low WC is safe for 1-2 years at least, then I'm fine.

 

[Tom Barr]

Well ,poerhaps glucinate would be better, just because DTPA is fine without water changes, does not imply the other chelator is less/better either, or that there's no differences.

Regards,
Tom Barr

 

[jonny_ftm]

I fully agree with this

A last question: if when dosing Fe in tank you have a good reading, does this imply necessarely that enough Fe is available and no need for further dosing?

 

[jonny_ftm]

Maybe I was not clear:

I begun dosing CSM+B alone. Now, my Fe is 1ppm. Does this mean I have 1ppm iron available to my plants or it can be as other unavailable forms.

By the way, this is to compare to my previous dosing with TPN where I always kept 0.1-0.2 ppm without issues

So, when my tank shows 1ppm, can I just stop dosing micro or should I continue (I only do a 50% WC every 3 weeks now)

 

[borman]

Thanks a lot Tom, guys

Now its much clear situation in my mind. So to finalize, if I made correct conclusions.
Better to combine gluconate (dayly dosing whel light is on) with EDTA Fe (cause i have quite low ph and have no ability to buy DTPA)
So only one qustion - how oftetn to dose EDTA fe?.
Regards
Larry

 

[jonny_ftm]

So,

Anyone can help saying if dosed Fe in water with test kits is the Fe potentially available to plants or can be other kinds of unavailable Fe despite a good dosage with test kit?

 

[Neil Frank]

LaMotte Fe Test

The simple iron test kits may not detect chelated iron.
I wrote to LaMotte inquiring about a test for aquaous Fe(II) plus Fe-EDTA, low range, indicating that I
would be happy with the total amount. I also inquired if their tests detect Fe-EDTA.

Here is the reply that i received from Richard LaMotte

"we checked with several staff here and could not find a suitable option for you in our product line"​

I suspect that the tests for Fe(II) will detect Fe gluconate, and if allowed to stand long enough may also see FeEDTA (due to photosensitiviy). LaMotte's reply suggests that there's may not be reliable or able to detect stronger chelators.

 

[Wet]

"So, when my tank shows 1ppm, can I just stop dosing micro or should I continue (I only do a 50% WC every 3 weeks now)"

I may misunderstand this question, jonny_ftm, but for clarity it is important to note that Fe levels in traces are only a proxy for all trace levels. So, let's say your tank uptake Mn from CSM+B -- having Fe available does not mean Mn is available. This is where the regular input crowd will yell "See!"

I like Tom's points about using different chelators of varying strengths as a sort of staggered approach. I will be trying this in a couple weeks (other experiments with EDDHA at a hobbyist level first) but believe barbarossa4122 is now.

I'm sorry I do not check multiple forums and especially this one in some time. Time forces me to be mostly monogamous with aquatic forums. But for those not on APC, here's some things about EDDHA as Sprint 138 copied over:

What we know about EDDHA chelated Fe (Sprint 138, aka "Super Iron")

6.0% EDDHA Chelated Fe. The label looks like this:

Default
What we know about EDDHA chelated Fe (Sprint 138, aka "Super Iron")

6.0% EDDHA Chelated Fe. The label looks like this:
This image has been resized. Click this bar to view the full image. The original image is sized 800x600.


It is a very dark substance that will stain the water. The left is a large (~1.0ppm into 20 gallons) wet dose and the right the trial/experiment sample of dry. I am sorry for the cellphone pics. I'll update these images this weekend if you'd like.

Weight trials (10) for 1 leveled teaspoon (5mL) show a density of 2.42 grams per 5mL.

Trials (scale accurate to 10mg)
2.42g
2.42g
2.43g
2.42g
2.42g
2.42g
2.42g
2.42g
2.43g
2.42g

So,

about 1/8tsp adds 0.2ppm Fe into 25 gallons.
about 1/16tsp adds 0.1ppm Fe into 25 gallons.

Here is a calculator I built that does Plantex CSM+B, Miller, 10% DTPA and 6% EDDHA Fe
http://wet.biggiantnerds.com/fe_calc.pl

At 0.2ppm Fe it will color the water pink. Certainly gets your plants redder looking ... an optimist might call it a free 9325K effect This video is currently being processed by YouTube but has a test of 0.2 ppm Fe into my tank. It still retained a pink tint ~12 hours later.
http://go.aquaticplantcentral.com/?id=673X1261&url=http://www.youtube.com/watch?v=ZCTu8ClcMKc

I am going to continue to experiment with this chelator. However, the side effects probably mean we have to use it at a low concentration, which may mean it can only be a supplement to other sources of Iron. For example, Tropica uses some percentage of DTPA and HEEDTA in their solutions, and Tropica Master Grow is a pinkish purple that does not noticeably tint the water column after 5 minutes of dosing. I can continue updating in this thread if there is interest else I'm sure I'll post about it in whatever threads it is relevant in

... and here's 0.02ppm dosed into my tank (forgive the mess) and 10mg into a cup with exact light (nfrank's request for a photosensitivity test):

and the same 3 days later:

 

[Tom Barr]

I fully agree with this

A last question: if when dosing Fe in tank you have a good reading, does this imply necessarely that enough Fe is available and no need for further dosing?

No

Regards,
Tom Barr