trace dosing

Cornhusker

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Jan 23, 2005
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tom, after water change you say to add traces next day. do trace elements get neutralized when dosed at time of nitrate and phospates? i've read this before about the NEXT DAY. thank you , cornhusker :confused:
 

Laith

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Jan 24, 2005
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Re: trace dosing

Mixing Fe and Phosphates together can lead to the Fe precipitating out into Iron phophate. This, as I understand it, is not usable by plants...
 

Laith

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Re: trace dosing

Ah, but the original PMDD "formula" had no phosphates! ;)

The concept was to limit phosphates as it was thought at the time that phosphates caused algae....
 

Ian H

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Jan 24, 2005
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Re: trace dosing

Laith said:
Mixing Fe and Phosphates together can lead to the Fe precipitating out into Iron phophate. This, as I understand it, is not usable by plants...

I'm not sure that this would be correct. If it was then just by adding iron you could reduce phosphate levels.

Ian
 

Tom Barr

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Jan 23, 2005
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Re: trace dosing

They add iron to lakes to remove the PO4 out of the water column..........

This reduces phytoplankton

But then the FePO4 drops into the substrate and is reduced and allowed to flux back into the system, then is oxidized again and reprecipitated back out.

The FePO4 will eventually be used by the plants and/or be exported.

Regards,
Tom Barr
 

Cornhusker

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Jan 23, 2005
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Re: trace dosing

:) tom, then what your saying is that kno3.potassium, phospate, and trace should not be mixed together in container of water and dosed same day. i have allways put alll these ingredients together in container of ro water and dosed. is this wrong? thank you,cornhusker :confused:
 

Tom Barr

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Re: trace dosing

I certainly would not mix the macors and the trace togather then add it.

I always add the the macro's dry anyway.
Then dose the trace liquid.

You can try this, take some water from the tank and put in a small glass, add some KH2PO4 and then add a few drops of Traces.........what do you see?

I know the practical is not that big of a deal but the theory behind it will not hurt and may help some.

Saves more on the traces which tend to be the most expensive part of dosing.




Regards,
Tom Barr
 

Cornhusker

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Jan 23, 2005
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Re: trace dosing

tom, ;) thank you for clarifying that. i am going to start dosing dry. also you mention not dosing potassium at all ? or just sometimes. i have allways dosed once a week after water change. 1 1/2 tsp for 75 gal. tank and 1 tsp for 55. is there enough potassium in kno3 to do the trick?
thank you, cornhusker
 

Ian H

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Jan 24, 2005
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Shipley, West Yorkshire, UK
Re: trace dosing

Sorry but I am still confused by this. As most fish tanks have some degree of phosphate content then any addition of Fe would produce FePO4 would it not?

Or is it just the higher concerntrations of the PMDD that do this. If not then I see no difference as to when it's added.

Also my PMDD formular contains no KH2PO4 so do I have the outlined problem? Should I separate the traces on this basis? My fish area looks like an alchemists store already. :)

Ian
 

m lemay

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Jan 23, 2005
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Re: trace dosing

The higher the concentration of PO4 is in a solution the more likely that you'll have a reaction with Fe. So yes in a fish tank with average levels of PO4 it is more likely that the plants will get to use the fe before it reacts with po4, Where as in a dosing solution, po4 levels are much higher and dwell time is much longer(sitting in a bottle for weeks at a time), this is a perfect environment for a reaction to FePo4.


Marcel
 

Greg Watson

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Jan 23, 2005
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Re: trace dosing

Ian H said:
My fish area looks like an alchemists store already. :)

Ian

I saw the neatest setup at a fish show recently ... it was a 55 gallon on one of those black wroght iron stands ... underneath it, on the bottom shelf, was a really attractive Picnic Basket ... inside the picnic basket was a wide array of "supplies" .... one of the neatest ideas I've seen in quite some time ...

Now I wonder why I thought it was the neatest setup ?????????

Greg
 

Ian H

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Jan 24, 2005
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Re: trace dosing

m lemay said:
The higher the concentration of PO4 is in a solution the more likely that you'll have a reaction with Fe. So yes in a fish tank with average levels of PO4 it is more likely that the plants will get to use the fe before it reacts with po4, Where as in a dosing solution, po4 levels are much higher and dwell time is much longer(sitting in a bottle for weeks at a time), this is a perfect environment for a reaction to FePo4.


Marcel
As my PMDD mix contains no PO4 compounds can I safely assume that my traces within the mix are not being compromised?

Ian