if you have more than one, and probably even if you only have one, they will more than likely kill him. They may not kill him now, but eventually they will. Do you have another tank you can put him in?
I paid $16 for my 6" one...so that a steal...ive rarely seen shovelnoses sold in pet stores...the biggest one ive seen was at Waldorf Pet Shop for $14 it was 7 1/2 inches and I bought it immidieatley.