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What is Hydroponics? Do It Yourself Growing Media Plant Foods Starting Formula This Page >> Hints for Success Operating Your System pH for the Gardener Finding Supplies F.A.Q. Hydroponic Links Cylindra Beetroot and Pickling Gherkin seed packets. Click the image to enlarge. Three Pickling Gherkins let to grow as cucumbers. Click the image to enlarge. Cylindra Beetroot about half grown. After cooking most slices are the same size. Click the image to enlarge. |
The discussion on this page is fairly technical, so if you are not interested in designing your own formulations or looking at the analysis for the Starting Formula on the previous page, you may want to go to the next page.
It is essential that the macro fertilizers be analysed in designing a new formulation. The Trace Elements are present as traces and will not be analysed here ... but do not forget them, or your results may be disappointing, unless your water supply can provide them. Along with the macro fertilizers in the Starting Formulation, Potassium Sulphate, Urea and Sulphate of Ammonia will be analysed as well. The latter two are not suitable for hydroponics, but are widely used for in-ground gardening. Mono Ammonium Phosphate:
Also known as Ammonium Dihydrogen Phosphate.
Calcium Nitrate:
Potassium Nitrate:
Magnesium Sulphate:
Also known as Epsom's Salts.
Potassium Sulphate:
Also known as Sulphate of Potash.
Urea:
Ammonium Sulphate:
Also known as Sulphate of Ammonia.
Now to calculate the fertilizer active materials to make up 160 Litres of nutrient solution for the reservoir tank.
Now, 160 mL = 4.0% of 4.0 Litres. Therefore solid Magnesium Sulphate = 4.0% 0f 1000 g = 40 g. Therefore Magnesium = 9.86% of 40 g = 3.94 g, and Sulphur = 13.0% of 40 g = 5.2 g.
Now, 320 mL = 8.0% of 4.0 Litres. Therefore solid MAP = 8.0% of 400 g = 32 g. Therefore Phosphorus = 26.92% of 32 g = 8.61 g, and Nitrogen = 12.17% of 32 g = 3.89 g.
Now, 640 mL = 16.0% of 4.0 Litres. Therefore solid Calcium Nitrate = 16.0% of 1000 g = 160 g. Therefore Calcium = 16.97% of 160 g = 27.15 g, and Nitrogen = 11.86% of 160 g = 18.97 g.
Now, 960 ml = 24.0% of 4.0 Litres. Therefore solid Potassium Nitrate = 24.0% of 400 g = 96 g. Therefore Potassium = 38.6% of 96.0 g = 37.0 g, and Nitrogen = 13.85% of 96.0 g = 13.3 g. Adding all of the active materials from the calculations above and tabulating them to show the amount present in 160 Litres of nutrient solution, the respective concentrations in milligrams per Litre and the recommended limits in milligrams per Litre, shown in brackets, we have:
The analysis above clearly shows that Magnesium and Sulphur are just above their lower recommended limits, so if you were re-designing this formula, it would be feasible to increase the Magnesium Sulphate (Epsom's Salts) content. If you need clarification on any points, please feel free to E-mail me. The next page shows Hints for Success. It brings everything together and fills in a few points that were omitted elsewhere. |