Water Care Water quality is very important, the water must be able to deliver dissolved nutrients to plants. If the levels of mineral salt are too high, then it is unable to dissolve the nutrients your plant needs. If the pH level is not between 5.8 and 6.2 then it can do the same thing, not allow the nutrients to dissolve. You can use chemicals to adjust the pH into the ideal range. Normal water temperature should be in the range between 65 degrees and 80 degrees to keep the plants thriving.