Yellow Water

Biollante

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Hi All,

I have been asked a question regarding CSM+B and yellow water.

I have never seen yellowing of water beyond concentrated mixtures, but I use a lot of peat in my substrates so it is possible this is common and I just have not noticed or am not sensitive to the discoloration.

Another possibility that occurred to me was lighting, my lighting is in the sunlight, high ambient and 5000 k to 9325 k ranges, those ranges may tint the water differently.

A suggestion had been made regarding a change from EDTA to DTPA chelate. I just do not understand enough to know why EDTA would discolor the water and DPTA would not. I have used both and I do not recall a difference in water color.

I think I recall reading something about certain water types reacting with CSM+B.

Any thought would be appreciated.

Biollante
 

Philosophos

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Looks like I'm not the only one dna has been messaging. ;)

EDTA disassociates from Fe much more easily at higher pH values. I've heard below 6pH is ideal. I'm guessing the Fe EDTA turns to FeO, which has such a nice color that it's used as pigment. The same thing would probably happen if DPTA disassociated as easily.

-Philosophos
 

Tom Barr

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Quit peeing in the water, it'll stop turning yellow.

ETDA is poor at higher KH's, use DTPA


Regards,
Tom Barr
 

Biollante

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Not In the Tanks!

Tom Barr;42455 said:
Quit peeing in the water, it'll stop turning yellow.

ETDA is poor at higher KH's, use DTPA


Regards,
Tom Barr

Thanks guys and I will try to remember!:eek:

Biollante
 

Tom Barr

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Well, there is the whole cat litter approach.
Using cat litter as a sediment base, then the cat goes in the tank, this fertilizes the plants, and no need to dose.

I do not think ETDA will yellow the water really.
DTPA is more red in color with some yellow.

We only add a little so I do not think there's much if any color effect our eyes can pick up, if you dosed say 100mls per 80 liters of tank, then sure..........

Regards,
Tom Barr
 

Philosophos

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So I just looked down a 12ml test tube containing 1.5ppm Fe EDTA and my 7kh tap water. Even with only about 5.5cm of depth to look through, the water in the EDTA test tube is more hazy, with a slight yellowish-brown tinge to it.

I've got a 500ml solution of 1.5ppm FeEDTA in local tap water sitting to disassociate further; in my observations of the tanks I dose, it takes a few hours to become more noticable.

If the effects don't match the tank water by tommorow, then I'll start looking to my aquasoil for tannin leeching, and testing it.

-Philosophos
 

DaBub

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Oct 18, 2009
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When you guys say high KH, what do mean?

I have about 10dKH.

I am trying what you did with iron chelated with EDTA. I see the hazyness as well.

I will see if I can get some iron with DPTA.

Two of my tanks have lots of tannins in the substrates so they always look darker.

In my gravel tank I do not see any 'yellowing' and I dose high on the iron with CSM+B and some extra Fe EDTA.