Feb,
I think a bubbler would work fine in two feet of water. They are so damn cheap to run, you can't afford not to use it! It costs me about $25 to run a 6 cfm compressor for the entire ice season.
In any case, always use a thermostat to control the compressor/circulator.
Check out the thread "De-Icers" by egatlake on 5-12-6 (
http://www.winnipesaukee.com/forums/...ead.php?t=2434) You can see me rant & rave about the virtues of a bubbler. I can't dispute the additional work to set up a bubbler ..... but this kind of work is fun at the lake ..... actually, everything is fun at the lake!
J