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Has anyone had a problem with Seachem Iron precipitating and turning the water cloudy.

I have a 72 bow that gets cloudy every time that I dose iron, and a 29 that doesn't. Beats me. Any suggestions?
 

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Iron precipitating

What can precipitate iron are:
The time required for uncomplexed ferrous iron to undergo oxidation to the ferric state is dependent on many factors, the dominant being: pH; temperature; dissolved oxygen level; and the presence of other soluble ions. The lower the pH and temperature the longer the time required for completion of the oxidation reaction. Increasing dissolved oxygen decreases the time required for oxidation. For example:

At pH 7.0, 90% Fe+2 oxidation requires 1 hour at 21o C and
10 hours at 5o C. At 21o C
At pH 8.0, 90% Fe+2 oxidation occurs in 30 seconds,
at pH 6.0 it requires 100 hours.
The critical dissolved oxygen concentration is 2 mg/L. Below that ferrous iron oxidation occurs slowly.
coming from http://2the4.net/iron.htm

What will precipitate iron faster is:
Higher PH,
Higher Temperature
Lot of oxygenation
 

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I'm no chemist, but isn't the iron in Seachem Iron complexed/chelated/whatever? I've never used it, but I have never had the chelated iron in Seachem Flourish precipitate by itself, only once when I got lazy and dosed macros and micros at the same time.
 

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I'm assuming you've read up on iron. So what's causing this? :p
It's a sliding scale... In my case (and I am just one of many many cases), I concluded that UV light (from my Coralife TT UVS) was causing the precipitation - in MY tank. UVS off, Fe tested 0 - clear water. UVS on, Fe tested 0 - clear water. UVS off, Fe added (3 different varieties - 3 separate exercises - dosed.5ppm Fe - test confirmed concentration) - clear water. UVS on, Fe added - hazy water for 48 hours. When water cleared after two days, Fe was tested - 0ppm. *If Fe was dosed, and the UVS was left off, Fe stayed in measureable amounts for weeks.

Conclusion - my UVS was precipitating Fe (Seachem, Kent, Homemade EDTA) in MY tank.
 

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Uv light

Uv light oxidize everithing and precipitate iron and other oxydes

Iron is oxidyze by oxygenation or UV Light
 

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If your kh is high enough, you will get a precipitate after adding Flourish. Seachem will even verify this for you, if you ask them. Mine is kh10, and I add it in the AM so I don't have to see the cloudy tank in the afternoon when I'm home. The cloudiness usually goes away in a couple of hours. If you use Greg Watson's (whoever the new owner is) iron chelate, the precipitation does not occur. The chelator in Flourish is gluconate, I believe, while the other is different and does not cause precipitation.
 
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