If you are getting detectable PO4
in your RO
water then it is time to change out the filters and membrane. I believe the actual membrane and DI
resin are responsible for removing PO4
. I have used Chemi-Clean and it is a great product. However, it will only remove the exsisiting cycno from your tank. It will do nothing to keep it from coming back. It is important to identify the source of the cyno and correct it to prevent further oubreaks. Try doing water changes with high quality RO
water, cut back on lights and food, add more flow to your tank and crank up the skimmer first.