Just add it to your cgminer.conf, like this:
"pools" : [
{
"url" : "stratum+tcp://middlecoin.com:3333",
"user" : "1E5PLsiUEzGqfLoLx5d1xpHF79jETTZcws",
"pass" : "x"
},
{
"url" : "stratum+tcp://eu.middlecoin.com:3333",
"user" : "1E5PLsiUEzGqfLoLx5d1xpHF79jETTZcws",
"pass" : "y"
}
]
You can add as many as you want.
You can also do stuff like auto-balance (mines all pools simultaneously), or failover-only, which starts at the top of your list and works its way down as servers fail. Google for cgminer.conf options and you'll get more details if you need it.
Is it possible to do this without editing the .conf file? I wouldn't want to bother doing that. Would I have to change the startup command if I did edit the .conf file?