# Mixing dry fertilizers together



## waj8 (6 Dec 2010)

I have mixed my dry fertilizers together including the trace mix and Macros. I did a one month supply so I can dose my tank daily using a teaspoon. Are there any issues with mixing these chemicals together dry?


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## Dolly Sprint 16v (6 Dec 2010)

waj8 said:
			
		

> I have mixed my dry fertilizers together including the trace mix and Macros. I did a one month supply so I can dose my tank daily using a teaspoon. Are there any issues with mixing these chemicals together dry?




Hi Waj8

Its advisable to keep them seperate and dose seperate - I think the trace and Kh2po4 dont mix very well - counter react with one another - Clive (Ceg) the best one to ask about this.

Found it - viewtopic.php?f=11&t=11396&p=121354&hilit=+mixing#p121354

Regards
Paul.


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## ceg4048 (6 Dec 2010)

Ideally, you should separate the trace powder from the NPK powders and dose them separately. The Iron in the trace mix and the Phosphate in the NPK mix can combine when placed in water to form a precipitate which then falls out of solution, making the Iron and PO4 less bio-available. Commercial all-in-one mixes use other chemicals (such as acids and chelators) in the mix to prevent this from happening, or at least to slow it down. In home made mixes one can simply dose the two mixes on separate days or at least within a few hours of each other to slow this process.

Cheers,


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## waj8 (6 Dec 2010)

I have been using James' all in one fertilizer right now without issue. I never see any precipitate with that mixture. My tank pH is pretty low as well at around 6.4 too, which should slow the reaction. Just thought it might be a little bit easier to mix the dry ingredients together. Guess I will stick with the all in one. Thanks for the replies. Great EI write up BTW ceg4048. I had never seen that particular article before and think it's the best one I have read.


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## ceg4048 (7 Dec 2010)

Thanks for the kind words mate. Glad you find the data useful. 8)  If you check James recipe you 'll notice that it calls for the following additives:
E300 Ascorbic Acid
E202 Potassium Sorbate
These are added specifically to combat the issue of Fe and PO4 interaction. As in so many things there is no absolute guarantee that the components will combine to form precipitates. Some people add NPK and trace at the same time and simply add them at opposite ends of the tank. You can try it and see if it makes any difference in your case. The fact is that there is a high probability of these components causing a precipitate and that's enough of a risk to motivate us to develop a rule of thumb to help keep us out of trouble.

In any case, James' all-in-one is really just another permutation of an EI recipe if you compare the ingredients. This differs from the Tropica all-in-one (TPN+) because Tropica derives a percentage of it's Nitrogen from small quantities of an ammonium salt, whereas James' recipe simply uses KNO3 in lieu of NH4NO3.

Cheers,


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## waj8 (7 Dec 2010)

I do add those two ingredients. I was just hoping that mixing the ingredients dry would prevent problems without adding those two items.  Doesn't seem like such a good idea anymore though.


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## ceg4048 (7 Dec 2010)

No mate, it isn't. Dry doesn't matter. It's when they get wet that the damage is done...  

Cheers,


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