# Iron Chelate-Sequestrene 138



## rgoodkind (Jul 8, 2005)

Has anyone dosed their plant tank using the iron chelate -Sequestrene 138?
What info can you pass on regarding this product?


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## watersoluble (Feb 21, 2010)

I have not used this stuff in my tank. But from what I just read it is chelated with eddha. Which turns the water pinkish even at .1ppm. As a Chelator though it is very effective across a broad pH range. See this Chart.


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## wet (Nov 24, 2008)

hey rgoodkind,

watersoluble is correct -- Here's the original post documenting when we first used this in an aquarium, including mass per levelled tsp: http://www.aquaticplantcentral.com/forumapc/fertilizing/67958-chelated-iron-yes-no-2.html#post521730

Those calculations (teaspoon or mg/g) are on http://calc.petalphile.com (and the depreciated http://wet.biggiantnerds.com/fe_calc.pl ) if you want them or to mess around with this stuff.

Here's some examples of what "pink" means. A video of the first time I dosed it into my aquarium:





Here's another example over time. There's two samples here - the tank, which a 40 breeder (so maybe 15-20 gallons in this paludarium-mode) and the cup, which has a small dose.

The cup has several layers of saran wrap ruberbanded over the top; we were trying to see whether Fe uptake (sample 1) or light (sample 2) would affect the red coloration. Notice the cup does become less pink and you stop being able to see the color in the tank.

Here's day 1.









Here's day 3.









Here's day 8. The guy on the left was the one floating in my tank, the right a fresh batch.









There's some argument to be made to mix this stuff with other chelated forms of Fe in such proportions that the water does not noticeably change color. For what it's worth, a few of us group-buyed this *for the sake of science!* (  ) but I don't think any of us use it anymore. I don't.

I'll send you some if you want, if I ever make it to the P.O....

HTH


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## HeyPK (Jan 23, 2004)

Here is a picture of a test I did on iron EDTA vs. iron EDDHA with _Ceratophyllum_. I think that one reason that the EDDHA did so much better is that iron EDTA tends to precipitate out in light, whereas it stays in solution in the dark.


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## rgoodkind (Jul 8, 2005)

Thanks for the information. It answers the questions I had regarding this chelated Iron.


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