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Re: Trying to figure out PMDD

Sam wrote:

"I bought trace mix and it does not match the %'s on the PMDD page. Here's
the breakdown:

FE 5.0%
Copper .25%
Boron .02%
Mg .50%
Mn .25%
Zinc .50%

Is this good? I was going to add 1 tablespoon of this to:

1 tablespoon epsom salts
2 tablespoons K2SO4
1/2 liter water

I have a 75 gallon tank and was going to dose 1 ml a day."
If you are using:


as the comparator, then you get:

 CSM            CSM+B      What you have
 Fe  7.0%          6.53%      5.0%
 Mn  2.0%        1.87%      .25%
 Mg  1.5%        1.40%     .50%
 Zn  0.4%          0.37%     .50%
 Cu  0.1%         0.09%      .25%
 Mo  0.05%      0.05%
 B  0.0%           1.18%      .02%

The difference is probably a result of differences of 'expert' company staff
opinion about the needs of plants. Maybe Paul Sears can speak to this. My
non-expert opinion is that the levels are so small to begin with, that it
won't make much difference. Note that the numbers for Fe are pretty close.
The concept at work here is that if we dose a properly balanced micro-mix
such that Fe is right, then all the other micros will fall in line because
they are mixed in proper proportion to Fe. But there may be disagreement as
to what the 'proper' proportion really is. So don't sweat this too much.

Adding Epsom salts will increase Mg, which is low according to the above
chart, so maybe that's a good thing. I'd check your water source report and
see what the Mg levels are out of the tap. But also:



to determine the MgSO4+7H2O (Epsom salts), K2SO4, and KNO3 doses.