user manager, please help me master ...!!

how to set a quota bandwidth of 1 gb / person with 1mbps speed, but after quota 1 gb / person expires, the rate dropped to 1kbps …?
please answer to the master…!!

pls follow the both link for your answer.

http://forum.mikrotik.com/t/recharge-an-userman-account-with-pin-password/58976/1

http://forum.mikrotik.com/t/i-need-a-scripts-automatic-change-ip-pool-1-to-ip-pool/63959/1


Best regards