How do i convert 220v to 12v without a transformer

Are you trying to kill yourself and others??  If your circuit FAILS, and WHEN, the motor will likely take the full voltage which means you have 220v on the pump motor, hence you may electrify your little system. And then don't touch it or you might DIE,  with 110 your muscles react with an open hand, on the other hand, 220 will make your muscles grab on, well you get the picture. I used to work as an electrician, and whenever when I was messing about with 220 (live) I always had an extra person holding me with a rope to my belt. or standing on a rubber mat, with rubber gloves and an apron. SO JUST Buy a wall wart.  Because I knew what I was doing I and two other guys changed out everything from the  3 Federal Pacific boxes that always ran hot (they lost their certification), to Square D and everything  was powered by 2 pole pigs (transformers) which were tied together where the boxes were. 

Are you trying to kill yourself and others??  If your circuit FAILS, and WHEN, the motor will likely take the full voltage which means you have 220v on the pump motor, hence you may electrify your little system. And then don't touch it or you might DIE,  with 110 your muscles react with an open hand, on the other hand, 220 will make your muscles grab on, well you get the picture. I used to work as an electrician, and whenever when I was messing about with 220 (live) I always had an extra person holding me with a rope to my belt. or standing on a rubber mat, with rubber gloves and an apron. SO JUST Buy a wall wart.  Because I knew what I was doing I and two other guys changed out everything from the  3 Federal Pacific boxes that always ran hot (they lost their certification), to Square D and everything  was powered by 2 pole pigs (transformers) which were tied together where the boxes were. 

Your concern has merit. Being able to do it doesn't necessarily mean you should do it. I thought a 12V wall wart would solve the problem. That is the solution I opted for when the door bell PS went south. Still ringing to this day....sorry got to go someone at the door.