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  1. [F][P] What's in my Fe homebrew?
    by (James B. Harold) (Thu, 3 Sep 1992)
  2. [F][P] What's in my Fe homebrew?
    by (Fred Kratky) (4 Sep 92)
  3. Laterite -- Overdose?)
    by (chris biow) (4 Oct 92)
  4. Plant Problems in Freshwater Tank
    by (Hans Ulrich Kaufl) (9 Aug 93)
  5. Iron solubility
    by Elizabeth Worobel <eworobe-at-cc.UManitoba.CA> (Mon, 25 Mar 1996)
  6. iron
    by eworobe/cc.UManitoba.CA (Tue, 10 Nov 1998)
  7. Aquatic Plants Digest V4 #246
    by krombhol/ (Paul Krombholz) (Fri, 28 Apr 2000)
  8. RE: FE
    by "Thomas Barr" <tcbiii/> (Fri, 05 May 2000)

[F][P] What's in my Fe homebrew?

by (James B. Harold)
Date: Thu, 3 Sep 1992
Newsgroup: alt.aquaria,rec.aquaria

Hi all.  I've gotta question:

For some time now, I've been mixing small batches of Wymex
FW trace elements and Wymex Fe together in a small bottle.  That 
way I just add a few ml a day of the mix.  A few months
ago I started using chelated Fe from a nursery instead of
the Wymex (mixed up to form the same concentration as the
Wymex).  The bag swears it's just Fe (it does have some
chlorine, but after mixing the concentration is undetectable
by my tests).  Now I'm also adding some potash (K2O) to
my little mix.

Now for the question....there's something forming in my
bottle of mix.  Kind of cottony.  Sinks to the bottom of
the bottle.  Anybody have any idea what it might be?
A precipitate?  A fungus?  And why I've never seen it
before?  My fish try to eat it when some gets in the tank
(they'll try to eat pretty much anything :-) ), so I worry
a little.  If it's an Fe loving fungus of some sort, I was
wondering if the Wymex/Dupla/etc mixes might contain
chlorine to prevent this kind of thing (given how much
you add to a tank, it wouldn't really pose a threat to
your fish).  That might explain why they had chlorine in
the nursery Fe in the first place.

I have the vaguest memory that this might have been brought
up before, but I can't say for sure...



James Harold                 "There is always an easy solution to            every human problem -- neat, plausible,
                              and wrong."    --  H. L. Mencken 

[F][P] What's in my Fe homebrew?

by (Fred Kratky)
Date: 4 Sep 92
Newsgroup: alt.aquaria,rec.aquaria

In article <> (James B. Harold) writes:
>Hi all.  I've gotta question:
>For some time now, I've been mixing small batches of Wymex
>FW trace elements and Wymex Fe together in a small bottle.  That 
>way I just add a few ml a day of the mix.  A few months
>ago I started using chelated Fe from a nursery instead of
>the Wymex (mixed up to form the same concentration as the
>Wymex).  The bag swears it's just Fe (it does have some

1) a chelating (sp?) agent is added to the Fe to help keep it in

2) I believe that they ph ballance the liquid to help keep the trace
   elements in suspension (this is a guess based on the contents on
   the Sera Florina bottle and my experiences)

The cottony stuff is probably some of your trace elements coming out of

     ||  // // ,'/~~\'   Fred Kratky 
    /||/// //|' `\\\     Mortice Kern Systems Inc.     (519) 884-2251
   / | //_// ||\___/     35 King St. N., Waterloo, Ont., Can. N2J 2W9

Laterite -- Overdose?)

by (chris biow)
Date: 4 Oct 92

I've had an interesting time adding iron to my plant tank. I
had been using Ortho Greenol, a terrestrial plant trace element
solution. In order to keep detectable levels of iron in the tank
(at least .1ppm), I had to add about .5cc of Greenol every
other day. Since Greenol is about 6% Fe by weight, I would
estimate that I added a total of about a gram of Fe, total.

I recently ordered some DuplaPlant 24 drops, and put 4 drops in.
The Fe level shot up to .5ppm, and fell to .2ppm over about
a two week period. Adding two more drops has kept the Fe level
around .3ppm for two more weeks.

Speculation: The vast majority of the Greenol Fe was precipitated
out by the last remnants of NovAqua in the tank water (though
I have switched to AmQuel for the last four months). It stayed in
solid form in the gravel, filter, or whatever. ALthough the
DuplaPlant 24 has _less_ iron per weight, it must have a
chelating agent that is lacking in Greenol (EDTA?). Thus, the EDTA
in the tank acts as a catalyst, dissolving the stored iron.
The EDTA breaks down slowly, at the rate of 50% per two weeks.

Does that mean that DuplaPlant 24 is better? Not really; it's
iron so expensive you might as well be purchasing gold. But at
the rate of a drop a week in a 55gal tank, it makes sense to
use it in conjunction with a cheaper source of iron. Like
a rusty nail, maybe...                                                          

Plant Problems in Freshwater Tank

by (Hans Ulrich Kaufl)
Date: 9 Aug 93

In article <245dv9$>, (Jeff Westhead) writes:
> Howdy! I have a freshwater tank. It is well-populated with tetras, angelfish,
> catfish, and platys. My problem is that some of my plants are having real
> problems. Some drop leaves. The stems of others turn brown and turn into
> mush. I've got an under-gravel filter and a power filter. I use fertilizing
> pellets weekly (2 tablets weekly, tank is 20 gallons).
> Thanks,
>   Jeff.
Hi there!

What you describe looks like a deficiency in iron. I assume you got enough
light, good bulbs etc. The problem with the iron-fertilizing is somewhat
tricky: the plants can only incorporate it while it is doubly oxidized,
that means having a chemical formula Fe++, After a while all these iron
ions will become further oxidized into Fe+++ well known to everybody since it
is the final product if steel corrodes. Fe+++ , however, is of no use for your plants.  Therfore you cannot help your plants by immersing a corroded piece
of sheet-metal. If your under-gravel filter and the power-heads mix too much
oxygen into your water all the iron contained in the fertilizer will oxyidize
before it is of any use for the plants.

My suggestion is to phase out the power-heads and the under-gravel filter and
replace them by an under-gravel heater (to provide for circulation in the gravel) , fertilizing with tablets put into the gravel (so the algae can't benefit from the fertilizer) and going with a cannister type biological filter.

good luck


Iron solubility

by Elizabeth Worobel <eworobe-at-cc.UManitoba.CA>
Date: Mon, 25 Mar 1996

At pH values commonly seen in aquaria (6.5 to 8) the amount of FREE Fe+3 in 
solution is very low. Iron in oxygenated waters forms iron oxides and 
hydroxides that basically precipitate as rust. They coprecipitate 
phosphate and other metals. If you dont believe me, check a speciation 
chart for Fe in solution. Chelation is the only way to deliver adequate 
amounts of iron to plants via the water column. BTW EDTA complexes iron 
as the Ferric (+3) ion.
Biologically, the valence state of Fe makes all the difference in the 
world ... its precisely because of its redox properties that makes Fe one 
of the central atoms in photosynthesis and respiration.

dr. dave.


by eworobe/cc.UManitoba.CA
Date: Tue, 10 Nov 1998

Iron is tricky stuff. It is terrifically reactive and the ferric (Fe+3) 
ion is almost insoluble. I have no idea how the test kits work but a 
reputable test would remove chelated iron from the 'chelos' (from the 
greek word for claw) in order for it to produce a color. Of course most 
labs analyze with some kind of flame so chelation is not an issue. 
Personally, I wouldnt trust any iron test kit. I like Karens approach... 
look to your plants!



Aquatic Plants Digest V4 #246

by krombhol/ (Paul Krombholz)
Date: Fri, 28 Apr 2000

>Date: Tue, 25 Apr 2000 23:44:12 -0700 (PDT)
>From: Anh Thach <>
>Subject: Chelated Iron as fertilizer
>In a farm supply store, I saw chelated iron sold at $25 for a 5 lb. bag.
>Is it OK to use this chelated iron for aquatic plants? Is it as good as
>fertilizer solution sold in LFS?

If the chelating agent is diethylenetreamine pentaacetate (DPTA), it is an
excellent source of iron for planted tanks.  Dissolve one level teaspoon in
two cups of water, and dose your tank at the rate of one to two cc per
gallon.  Keep the solution in the refrigerator, and if it still tends to
grow some kind of underwater mold, boil it.  I find that it lasts in the
aquarium for months, and that I only have to add more every 6 months or so.
I do not use iron test kits, but go by the appearance of the plants.
However, if you make frequent water changes, you will have to dose the
newly added water.  You don't have to worry about conserving your supply,
with five pounds, you will have more than a lifetime supply.  You will
proably bequeath about 4.8 lbs to your offspring.

Paul Krombholz, in central Mississippi, where the trees are fully leafed
out, and all the summer birds are in place.  


by "Thomas Barr" <tcbiii/>
Date: Fri, 05 May 2000

>Tom Barr wrote  "What's your Fe? Check these first. Look in archives on
>Green water. Try Blackout/Micron filters
>like a HOT 250 magnum, get NO3 in the 5-10ppm range, Fe to .5-.7 or so..."
>Tom, I assume you meant 0.05-0.7, since the level suggested on the Flourish
>Iron level is 0.1 ppm and the range I usually see on this List is 0.05-0.1
>ppm. A search of the Archives turned up someone's: "Ooops, typing error.
>The iron level was between 0 and 0.05 mg/l, not 0.5 mg/l. Sorry."
>Note also the label for Karl Schoeler's Natural Gold fertilizer: "Add
>enough NATURAL GOLD to keep iron levels at .5 to .75 mg/l." 

I agree with Karl's range. Personally I have 1 to 2 ppm of Fe.  0.05 ppm is
way to low unless you wish to use Fe as a limited nutrient in a low
maintenance tank or something.  0.1 will give a OK result in a low light
tank, but at 2+ watts you likely don't have enough FE for your plants and
you will have better growth if you add more. Claus of Tropica adds about 3 x
time the recommend amounts and folks always wonder why my plants grow well.
I've been "over dosing for years".
I don't have excess algae. Other's on the list have confirmed some this
also. If you have a good balance between your PH/KH/light and algae is under
control you can do this 1ppm Fe. You can also do .2-.7ppm with no problems
if your a little more cautious. Your starving the plants when you try to
limit things too much. It's a balance, not a limited nutrient approach.
Heck, I have over 1ppm of PO4 also. Great plant growth. I've grown over 200
species like this. 
Many Companies recommend lesser amounts due to softer waters/new folks
adding too much etc and other issues that error on the cautious. I would
also, but might mention that these levels can be raised in a well run higher
light tank etc. Claus mentioned that mosty of the tanks he saw in SF were
nutrient deficient even though many had the .5ppm range. We started adding
more and guess what? Better richer greener growth.

Typo it is not. I feel it may be low but as you get the PH/KH/CO2 and the
light balance going well, then a nutrient balance is the next issue to
Tom Barr

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