jbj chiller

I have a JBJ CHILLER DBA-075 thats a year old. Runs great and looks clean. I just outgrew it unfortunately. I asking 475 for it and will ship. I bought it last year for 715$ shipped.

I’m looking at sicce pumps I was wondering if I could use the 0.5 without damaging the chiller or do I have to use the 1.0. The minimum flow rate is 240gph but I saw a thread on here where some said it would be ok to use the 0.5