Unfortunately, due to limits in the Radio Chip, you cannot assign more then one L2 ACL per WLAN/SSID so the limit is 128 MAC/Clients
The only option to control access via MAC address is to use MAC authentication which will require an external RADIUS server:
000001847 - mac authentication using radius server
13 Feb 2018
My Support Account ... mac authentication using radius server Summary ... How to configure MAC authentication with RADIUS ... How to configure MAC authentication using radius server?
000001247 - MAC address filtering compared to MAC authentication
11 Jan 2014
MAC authentication checks the MAC address of the clients against a RADIUS server, and allows connection to MAC that is listed. ... Once authenticated the client traffic is allowed to pass.
Another very good option would be to use the Ruckus DPSK mechanism that assigns a personal PSK key to each user and binds this to a specific client device MAC address
Check the administration guide for the version of ZD/Unleashed code you may be running for details and check out the Knowledge base on support log that has many articles on DPSK usage.
I hope this information is helpful,