With 5lb line you should be able to land a 10lb fish, depending on how adept you are at fishing, though most fisheries that i know will insist on minimum 6lb breaking strain.
As SKB said, check out the fishery rules re: breaking strain of fluorocarbon/mono i personally won't go below 6lb. Bear in mind lot's of stillwaters can have some big lumps of fish in them (hate to think of fish swimming around with stuck flies, and trailing mono)
My personal weapon of choice is a 9ft #6 rod, i find anything above that is overkill unless you're fishing Di7 or extra fast sinking lines or heavy lures.
Once you fish buzzers, you will never go back to the dark side
Best regards
Jim