Hey Dr_P,
FWIW I just tested an E-1250 and an E-1048 next to my 3 yr old Sony 19" Trinitron. Both pumps make the screen wiggle when sitting beside/ontop of the monitor. The 1048 seems to be a little stronger than the 1250.
Moving either pump 6" away greatly reduced the interference. Moving them more than a foot away eliminated it. Pumps are plugged into the same circuit as monitor.
I have to agree with Since87... both the pump and monitor are contributing to the problem. The pumps do emit EMI but a well sheilded monitor won't be too succeptable.
Move the pump farther away, try making a sheild for it or get a new monitor...
Good luck,