I brought home a stray cat 6 or 7 years ago, not realizing he had fleas. I went with Frontline and bombed the house as well. I covered all tanks, including the sump or anything else that is exposed to the air, with trash bags and duct tape, turned off the skimmer, and went ahead and bombed house with one "bomb" per room. Went out for the day with our other cat and the dog. I had no problems, but everything has to be cleaned top to bottom and ventilated well before you take the covers off the tanks and start your skimmer back up.