After adding the nutrients, let it settle for an hour or two before checking pH. Optimum pH range is 5.5-6.5 (6.0 is ideal) Keep the solution between 65-75 degrees (60 min, 80 max).

Maintaining the recommended pH levels for your hydro grow system is also key to your plants’ success. A slightly acidic pH will help promote the growth of beneficial fungi, which is great for weed.

Nutrient solution and solution pH influences on onion growth and mineral content, J. Plant Nutr. 2006; 29(2), 375 – 390. doi: 10.1080/01904160500477028. 11. Fakhrurroja H, Mardhotillah SA, Mahendra O, ...