after running this:
Code: 
[~]# iptables -I INPUT -p tcp --dport 80 -m connlimit --connlimit-above 20 --connlimit-mask 40 -j DROP
i get this:
Code: 
iptables v1.4.7: --connlimit-mask must be between 0 and 32
Try `iptables -h' or 'iptables --help' for more information.
also about mod_qos i have the excact same settings
Code: 
LoadModule qos_module /usr/lib/apache2/modules/mod_qos.so
Include "/usr/local/apache/conf/qos.conf"
Some times when i refresh my page, it returns nothing. its annoying while you post. also CT_LIMIT somehow bans some ips. i have set it to 50.