reduce speed

hello

i use MikroTik 3.30
i want to reduce speed after 500Mb dowenload

How?

show this url
http://wiki.mikrotik.com/wiki/Limiting_a_user_to_a_given_amount_of_traffic_II

but

i want to limit using queue tree Not simple queues

any help please

use /ip firewall mangle to mark packets, that bandwidth limit should be applied.
Use packet-mark in /queue tree.

have u got any solution same problem i have