I am planning to start growing using hydroponics. Unfortunately I'm unable to obtain fertilizers that are made specifically for hydroponics. However, I can get water-soluble fertilizers. The images of the fertilizers are attached. The one named Libro contains NPK + iron, and the one named Torofert contains Calcium, Nitrogen, Magnesium and Boron.

As you can see, the NPK formula is 20-20-20, while the calcium is 24% in the fertilizer named Torofert. Torofert also contains Nitrogen, which is 15%. I'm also going to add Epsom salt (contains Magnesium and Sulfur) to these two fertilizers.

Normally, people mix three fertilizers: first one contains NPK with a ratio of 4-18-38, second one contains calcium and nitrogen at a ratio of 15.5% Nitrogen and 19% calcium (no magnesium), and third one (Epsom salt) contains magnesium and sulfur.

Do you think the fertilizer mixes that I have are suitable for hydroponics? Will there be too much Nitrogen or Magnesium since each one of them is included in 2 of the 3 fertilizers? Do I need to consider anything else? enter image description here enter image description here

2 Answers 2


Short answer No,

Detailed answer - Here are the reasons why you should not use it for hydroponics

  1. These fertilizers are designed to be used in soil. They are slow releasing and the rate of release of individual nutritional element is not consistent.

  2. Mostly it uses Ammoniacal source of Nitrogen. Yes it can be consumed by plants directly but it is very poisonous even in slightly higher concentration. This source of nitrogen is designed to be broken by bacteria in soil first which does not happen in hydroponics. Mostly in hydroponics nitrates are used as source of nitrogen. Mostly calcium nitrate and potassium nitrate.

  3. It is very difficult to achieve desired concentration of nutritional elements with this kind of mix resulting into deficiency of some elements.

  4. The micronutrients are in form of oxide, notice the "O" in the formula. This type of micronutrients have issues with ion exchange and will result in complex salts which cannot be used by plants.

I guess this company also makes water soluble fertilizers http://hadaflevel.com.sa/#!/Straight-Fertilizers you can check this out. Probably this might help you.


I don't think so. I had issues with missing trace elements when I first started with hydroponics. I think you need a complete solution, unless you are growing in soil as a medium.

  • Thanks for the answer. What kind of issues did you have? Aside from the missing micro-nutrients, do you think that my overall Nitrogen levels (20 from Libro + 15 from Torofert = 35) would be too much? What about Magnesium and the fact that it is also coming from 2 sources?
    – Adam
    Sep 1, 2020 at 19:11
  • Also, can I add some mineral water to provide the missing trace elements?
    – Adam
    Sep 1, 2020 at 19:50
  • I used Geolite, which is ceramic. Lower leaves on all my different plants would yellow and drop off, while upper growth was great. Once I switched to a complete fertilizer, all was good. I am not sure on the mineral water.
    – Evil Elf
    Sep 2, 2020 at 0:12

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