reuse live sand?
 

i just got finished shutting down my 55 gallon and am considering using the tank for a sump under my 110 gallon, im wondering if it would be worthwhile to use the livesand from that set up as a deep sandbed in the sump? if so should i clean the sand first?

You can syphon th top half inch of sand, wash out the old stuff really well, then seed the new DSB with the sand you kept.