This Xtreme cleaning solution is for flushing continuous ink tubing (such as when you want to change ink types), or helps to resolve stubborn/extreme clogs in printheads. For printhead cleaning, this Xtreme cleaning solution is a last resort option.
First try the regular cleaning solution for printheads, as this XTREME solution is a stronger formula. Flush your print-heads with this solution (if your system is damper/CIS based), or fill it into "cleaning cartridges" and run up to 3 cleaning cycles with those cartridges (if your system is cartridge based).
