# ETDA, DTPA or HEEDTA?



## rybal (Jan 24, 2005)

Hi guys.
I’m going to make my own trace mix. So, I’d like know your opinion.
Which chelators are better (more suitable) for plants in high lighted tank?

-weaker – gluconate as chelator for Fe ?
(are plants able to more easily derive from it than from EDTA-?)
-more stable ETDA, DTPA?
-or the strongest chelator - HEEDTA ? 

Regards 
Tomas


----------



## plantbrain (Jan 23, 2004)

DTPA will likely suit your needs best as the pH range is well suited for our purposes.

Regards, 
Tom Barr


----------



## rybal (Jan 24, 2005)

Thanks Tom for replay!
Actually I use the liquid form of Trace Mix Chelated with HEEDTA, which is stable in the wide range of the pH (3-8 is the most effective in this range). Is the using of such strong chelator in so high lighted tank could cause the deficiency in plants (less plants’ growth, or?).

I mean, is HEEDTA too strong to be able to provide the recommended amounts of trace elements for plants? And, is it also depending on the used concentration of this chemical in the water?
Tomas


----------



## plantbrain (Jan 23, 2004)

It should work fine.........

Regards, 
Tom Barr


----------



## rybal (Jan 24, 2005)

Thanks Tom for response.
I'd back to discuss about chelates. 
I found this on Seachem web:http://www.seachem.com/products/product_pages/FlourishIron.html

"Flourish Iron™ is a highly concentrated (10,000 mg/L) ferrous iron (Fe+2) gluconate supplement. It should be used in those cases where the iron requirements exceed that which can be delivered by Flourish™ at the recommended dose or signs of iron deficiency appear (such as short and slender stems or yellowing between veins.) Plants are able to much more easily derive a benefit from Flourish Iron™ than from EDTA-iron sources because all EDTA iron is in the ferric (Fe+3) state. Since plants require iron in the ferrous state, additional physiological energy must be expended in order to extract the ferric iron from EDTA-iron and then convert it to the ferrous form."
Is it true?
Do you agree with it?
Regards 
Tom


----------



## niko (Jan 28, 2004)

Tomas,

You need to try what works best for you - both the type of chelator and the dosing regime.

A neighbour of mine and I have a hard time providing Iron to our plants. I use a mix of EDTA and DTPA. He usually uses HEEDTA and Fluorish Iron, and I gave him some EDTA and DTPA to try but nothing really changed. Our plants grow but stay a little pale all the time despite all the known water parameters being fine.

So try whatever you have and see.

--Nikolay


----------



## plantbrain (Jan 23, 2004)

As Niko says, most have trouble seeing a difference, there is a difference, but it's subtle(but present), and not entirely linked to the chelator in question either.........

Regards, 
Tom Barr

www.BarrReport.com


----------



## Milan (Jul 6, 2005)

Excuse me for maybe a silly question, but what are ETDA, DTPA and HEEDTA?


----------



## niko (Jan 28, 2004)

Milan,

The Iron that the plants need cannot be used by them as it is. For example if you drop a rusty nail in your tank that will not provide Iron for the plants. (I assume that the plants can actually use that Iron but not very well, Tom may shed light on that.)

So for the Iron to become usable to plants it has to be bound loosely with special molecules called "chelators". Some chelators are Citrate, Gluconate, EDTA, DTPA, HEEDTA. Basically you mix the Iron with a chelator of your choice and the iron becomes usable by the plants.

The bond between the chelator and the Iron is loose but some chelators bind stronger. That depends on different factors - the kind of the chelator and for example pH.

Practically it's best to try a few untill you find the one you like best.

--Nikolay


----------

