any way you could take a picture?
It sounds like it is just getting ticked off. One 24w 50/50 bulb isn't a whole lot of light over 6 gallons. Condys are fairly hardy and easy to take care of. What have you been feeding it? A lot of anemones need to be hand fed something meaty on a regular basis, especially Condylactis because not many clown species will take up residence in them and give them a share of the food.