Agriculture Reference
In-Depth Information
TABLE 5.1
A General Macronutrient Formulation for 10-U.S.-Gallon Tank
Weight/10-Gallon
Tank (gm)
Elements Supplied and
Concentration (ppm)
Fertilizer Salt
Calcium nitrate (Ca(NO
3
)
2
)
31
Ca: 180 ppm, N: 126 ppm
Potassium nitrate (KNO
3
)
4
K: 39 ppm, N: 14 ppm
Potassium sulfate (K
2
SO
4
)
23
K: 250 ppm, S: 102 ppm
Magnesium sulfate (MgSO
4
)
19
Mg: 50 ppm, S: 66 ppm
Monopotassium phosphate
(KH
2
PO
4
)
8.5
P: 50 ppm, K: 63 ppm
Totals
N: 140 ppm, P: 50 ppm, K: 352
ppm, Ca: 180 ppm, Mg: 50 ppm,
S: 168 ppm
weighing the compounds. The weight of the microelements will be even
smaller, so we need to make a concentrated stock solution with them and
then just add some of that prepared solution to your tank. You can purchase
a 10-gallon gasoline or water tank to store the micronutrient stock solu-
tion. Keep it in the dark away from direct heat to prevent algae growth.
Table 5.2 gives you the weights for a micronutrient stock solution of 300
times normal strength in a 10-gallon container.
For a 10-gallon nutrient tank you need to add: 10 × (1/300) = 0.0333
U.S. gallons of the micronutrient stock solution. That is in liters: 0.0333 ×
3.785 = 0.1262 liters or 126 milliliters (ml) (1000 ml = 1 liter). Purchase
a 100-ml graduated cylinder to measure this volume of solution. If you
cannot get the triple-beam scale and graduated cylinder from your local
hydroponic shop, contact a scientific laboratory supply company, such as
Fisher Scientific.
TABLE 5.2
A 300 Times Strength Micronutrient Stock Solution in
10-U.S.-Gallon Tank
Weight/10-Gallon
Tank (gm)
Elements Supplied and
Concentration (ppm)
Compound
Manganese sulfate (MnSO
4
)
41
Mn: 0.8 ppm
Copper sulfate (CuSO
4
)
3.2
Cu: 0.07 ppm
Zinc sulfate (ZnSO
4
)
5.5
Zn: 0.1 ppm
Boric acid (H
3
BO
3
)
20.5
B: 0.3 ppm
Ammonium molybdate
((NH
4
)
6
Mo
7
O
24
)
0.6
Mo: 0.03 ppm
