Hi,
To block communication between gateways try something like this (Network -> Firewall -> Custom Rules):
iptables -A INPUT -s 192.168.130.1/24 -d 192.168.150.1/24 -j DROP
iptables -A INPUT -d 192.168.130.1/24 -s 192.168.150.1/24 -j DROP
iptables -A INPUT -s 192.168.130.1/24 -d 192.168.170.1/24 -j DROP
iptables -A INPUT -d 192.168.130.1/24 -s 192.168.170.1/24 -j DROP
iptables -A INPUT -s 192.168.150.1/24 -d 192.168.170.1/24 -j DROP
iptables -A INPUT -d 192.168.150.1/24 -s 192.168.170.1/24 -j DROP