The fertilizer is a mixture or calcium nitrate, magnesium sulfate, and phosphate. You can buy these items separately and create your own mix, which is probably smart to to do on a large hydroponic garden, or you can buy it premixed like I do.
I use a 20-18-38 mix from Urban Hydroponic which I buy on Amazon.com. This is considered the “Master Blend” for tomatoes. I do also have peppers, beans, and zucchini in my garden getting the same fertilizer and even though this mix is not optimum for them it will still work. I would like to mention that all the nutrients I use ARE ORGANIC so all the vegetables I grow will be completely organic.
In the video you will hear me talk about “Parts Per Million” or PPM when I measure the fertilizer level in the mixture. What this means is there are X 1000 parts of dissolved nutrients (fertilizer) in the water. My PPM meter shows only three numbers so when I it goes over 1000 it shows a small x10 on the screen. So in this video my meter ended at 170 x10 which means I had 1700 PPM. It is probably more but I did not continue stirring it. I have an air stone in my reservoir and it will continue to mix the nutrients in. For an example of how clean the water in my rain barrel is, when I test it I get a measurement of 40 without the x10. So my rain water has 40 PPM of dissolved nutrients. To measure the PPM I use an Etekcity Digital Handheld TDS Meter. It will measure up to 9990 PPM.
I also pay close attention to the PH value, and acidity of the water. Again I set the PH value for the tomatoes which is between 6 and 6.8 (I say 6.5 and 7 in the video). The PH level for hydroponic gardens is the same for soil gardens. PH 7 is neutral and the acidity raises as the number value goes down.
Lastly I would just like to mention that this is my first ever garden and I am not a professional. If I have said something wrong in this article or in the video please let me know via the CONTACT page.