Dynamic default rooms?

[JMElmore]

I am pulling my hair out trying to figure this out.

I want to dynamically set the default channels from list of rooms in a database. If I manually type

$params["channels"] = array("room 1", "room2");
it will work...

If I do something like
$params["channels"] = array();
start for loop
$params["channels"] [] = "Room 1";
second time through loop
$params["channels"] [] = "Room2";
end loop

This does not work!

What is going on here?