Monitor displays differently from other monitor

My monitor color display is different from other monitor. My monitor has some violet gradient. What could cause this problem? Recently I cleaned my computers from dusts and disassembled my desktop computer to remove the dust that is inside the CPU and behind the monitor. My monitor is a CRT. If anyone has some answers, please help me with this one. My eyes are distracted and I can't work on my Desktop.
Thank you.
