Add two ip on wan interface ???

Hi i have read many topics about this topic and tested all not working. have a good network knowledge but do not configured mikrotik before. i have /27 subnet from isp now just one ip added to wan interface and everything is working i want add second ip and use it for web server.

first ip = just surf internet for users
second ip = web server redirection

my conf:
added second ip on interface
src-nat for first ip users
and serc-nat web servers ip to second ip on interface but do not working . please help

/ip firewall nat
add action=src-nat chain=srcnat src-address=webservernetwork/24 to-addresses=secondwanaddress
add action=dst-nat chain=dstnat dst-address=secondwanaddress to-addresses=webserveraddress