You should perform an SDI ... Published May 10, 2018 16:52 by Rafael Gay-de-Montella MSc PEng, Water Wastewater Treatment Expert, Oil-Gas, Tailings, Boilers, ZLD; Evaporators, Sludge You should perform an SDI test, and re-exam the situation when you have the results for at least three separate feedwater sample. If need help on this contact (no charge for guidance).