i agree with not moving him- you will just stress him out. i would go to lowes or home depot and buy a sheet of light diffuser (we all call it eggcrate). its in the lighting section. you can easily cut it to fit inside the tank. cut it so you can wedge it in the middle of the tank-clean that half of the tank.. then pull it out, move the jag to the half you just cleaned and put the section of eggcrate back in the middle so you can clean the other half.
thats what i would do..