General Hydroponics Pro pH adjusters are based on completely different technology than our traditional smaller sized adjusters offering. New non-mineral based acids and bases will not add nutrient value like the use of phosphoric acid or potassium hydroxide. They are safer to use as well as compared to mineral based adjusters. This is due to having a zero rating score for all safety categories on the HMIS scale as well as being non-corrosive and non-caustic. This means there are no HazMat fees to ship these products like other pH adjusters. Use Pro pH UP or Pro pH DOWN to effectively adjust the pH of nutrient solutions or irrigation water. GH Pro pH adjusters are highly concentrated and available in commercial sizes.