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End to PMDD Confusion

> I rumaged around the Krib today to see if
> I could figure out the 300ml vs 500ml
> solution confusion in PMDD formulas.
> Here's what I found. Looking under
> "Fertilizer" "General" then "Conlins-Sears"
> for their original paper, they present
> the original formula as:
> 
> - ------------------------------------------
> * 1 Tbsp (~9g) Chelated Trace Element Mix (7% Fe, 1.3% B, 2% Mn,
>     0.06% Mo, 0.4% Zn, 0.1% Cu, EDTA, DTPA)
> * 2 Tsp (~14g) K2SO4 (potassium sulfate)
> * 1 Tsp (~6g) KNO3 (potassium nitrate)
> * 2.5 Tbsp (~33g) MgSO4.7H2O (fully hydrated magnesium sulfate, aka
>    epsom salts; omit if already present in trace element mix)
> * 300mL distilled H2O
> * 0.5mL 9M HCl (optional)
> - -------------------------------------------
> 
> However, I kept going and under
> "later information" found the following:
> 
> - -------------------------------------------
> MORE COMMENTS REGARDING THE SEARS-CONLIN PAPER
> "3. Who sold PMDD"
> by Kevin Conlin <kcconlin at cae_ca>
> Date: Tue, 05 Nov 1996
> Newsgroup: rec.aquaria.freshwater.plants
> Tim Mullins wrote:
> > A little while ago someone posted a price
> > for suppling a pre-mixed PMDD for those
> > of us having trouble locating ingrediets.
> > Could you re-post or send me e-mail.
> [PacNeil at worldnet_att.net].  I can supply people in
> the Montreal area who are willing to come pick it
> up.
> 
> Incidentally, I've found that the following recipe works better now
> that my UV is off: 1 tbsp trace element mix, 1 tbsp epsom salts,
> 1 tbsp KNO3, and 2 tbsp K2SO4 in 500ml H2O.  If your nitrates are
> currently on the high side, hold off on the KNO3 until they
> drop to unmeasurable levels.
> 
> Kevin Conlin  Montreal, Canada  "We're Canadians.  We HAVE to be polite"
> Finger as332 at freenet_carleton.ca for PGP public key.
> - -------------------------------------------
> 
> So, it looks like this is the source of the
> confusion! Once Kevin switched all the
> ingredient amounts from teaspoons to tablespoons,
> he upped the water level from 300 ml to 500 ml.
> The great and powerful "Wizards of Canada"
> have spoken.  :-)
> 
> Many thanks to Pat Bowerman, who may have more
> say on this matter.
> Thanks,
> Tim Mullins - Pittsburgh

Tim, I agree. It appears that when Kevin e-mailed me his new formula, he
failed to mention that he changed the amount of water added. It would
appear that when Kevin switched to adding tablespoons of ingredients, he
also upped the H2O to 500ml.
Folks will notice that in the 500ml solution, there is less MgSO4 and
more K2SO4. Also, in the formula that Kevin e-mailed to me, he changed
the KNO3 to 2 tablespoons. He explained to me that many people had
experienced a shortage of K and N with the old formula. As for dosage
rates, I still say that you have to find what works best for _your_
tank. Because of the many variables involved, I don't see how one could
ever establish an x number of ml per gallon dosing formula. 
 
Thanks again Tim, for trying to get this straightened out. I hope that
this puts this to rest for a while. At least until we can hear from
Kevin or Paul, again. 
   
                                                                Pat
Bowerman