If you specify a IP for the container you should be able to remove the ip_range setting.
Hint: If you use DHCP in your network (like I am with my fritzbox) there is a setting in the fritzbox to see the range it sets there. When deploying dockercontainer on my macvlan network I give them IPs outside of the range (e.g. < .20) to not come into conflict with any dhcp assigned IPs.