The graph below shows the level of trace elements stability with different chelating agents at different pH levels. As you can see, EDDHA is the strongest chelate of any of the commonly used materials and maintains iron availability to plants past pH 9.0. However, other types of chelating agents can be used as long as pH conditions are suitable. EDTA is better suited to slightly lower than neutral pH levels. DTPA is most effective at slightly higher pH levels. Gro IT uses Potassium Citrate as a pH buffering agent as well as a chelating agent. The strongest and therefore most effective of the synthetic chelating agents is EDDHA. It is found only in select fertilization formulations because of its relatively high cost. Gro IT uses EDDHA and Potassium Citrate as chelates to enable maximum absorption of their laboratory grade trace elements, making Gro IT one of the most unique and effective nutrient line on the market. Plants supplied with adequate levels of EDDHA and Potassium Citrate are able to absorb more zinc than plants supplied with EDTA, which is very important as zinc is often locked out in the later part of flowering due to excessive phosphorous levels, causing plants to stress resulting in loss of yields.