SirFency

I hope I'm posting the the correct spot. I have a question I'm not even sure how to ask properly. I am experimenting with electrocoagulation, electro flocculation, and electroflotation in the pretreatment of wastewater. I need to achieve 20mA/cm2 in my electrolysis chamber. I dont really understand what this means. I have a 1500w bench style DC power supply. I connect it to Al and Fe electrodes. Is the formula referring to the surface area of the electrodes or the conductivity of the solution? I'm assuming this is referring to the surface area of the electrodes. If that is indeed the case how do I assure I'm achieving the desired current per surface area? Do I just set the DC power supply to 20mA? I doubt this is the case that sounds too simple. I have a surface area of 1,168.4cm2. Do I multiply the 20mA by the surface area? If thats the case I should be able to set my DC power supply to 23.368A and that should give me the 20mA/cm2 I'm Looking for correct? Thank you in advance for anyone that takes the time to read this.