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PMDD dosing

OK, I guess I am confused (again).

I mix PMDD using materials from Homegrown Hydroponics. I mix as follows:
into 1/2 liter RO water
1 tablespoon chelated trace mix
1 tablespoon MgSO4+7H2O
2 tablespoons K2SO4
into a separate 1/2 liter of RO water
1 tablespoon KNO3

I know the modified Sears/Conlin formula calls for 1/2 liter. Everything 
seems to stay in solution better if I mix them this way.

I am currently using a Kangaroo 330 enterral feeding pump to dose my 
solution. I do this to allow constant dosing of the chemicals, and to avoid 
having to mess with the chemicals daily. I mix 45 mls of each of the above 
solutions into 1 gallon (~ 3800 mls) of RO water, and set the pump 40 
mls/hour. The gallon jug lasts about 4 days at this rate.

Now for the source of my confusion.

Mullins states (from the Krib);
"If you have a "high tech", densely planted, CO2 injected, VHO lit tank, 
you might want to double the dose to 1/6 ml of PMDD per 10 gallons a day 
(roughly 4 drops)"

For my 70 gallon tank, that translates to slightly more that 1 ml/day (2 
mls/day since I use 2 solutions). I am dosing more than 11 mls\day of each 
solution (20 mls total), and still showing no iron residuals. My nitrate 
test is either contaminated or old, so I'm not sure what that concentration 
is.

Other tank parameters are
pH ~7.0
GH = 14
KH = 6
NO2 < 0.3
160 watts standard fluorescent lighting
CO2 - 15 to 20 ppm (from chart)

Plants include three really large sword plants (leaves 18 to 21 inches 
long), 4 medium to large anubias, 40 to 50 stems of anacharis, 40 top 50 
stems of bacopa, and 8 of what my LFS calls "Purple Crinkle", that is no 
longer purple on the underside of the leaves.

Am I missing something here? If not, does anyone else use doses this high?


Douglas Guynn
	dguynn at nwol_net
	915.368.5411

The Ancient Greeks were 100% correct about this concept: He who refuses to 
participate in self-government runs the risk of being governed by a fool 
greater than himself.

It was not a stunned silence that the world heard.  It was the quiet 
meditation of a warrior.