My bulbs are 6+ months and the " change bulb light" just came on. I actually have retired the machine for the summer, and will get going again in october so ill probably get a spare light or two so i have it on hand, but continue with the old ones until they go, or just arnt as efficient. Another thing about the tomatoes isthat their root system gets so intense, that u really have to pay close attention to the water levels ( and not the warning light). I would have to add water every other day( which is no big deal at all) but it seems the water sensor was not as sensitive as it should be ( or it might just be programmed to go off ever y few days depending which plant u have it set too). But either way, open up the lid and check the water level from time to time.
Oh, speaking of opening up the lid, my cat figured this out, and now i have to ban the cat " lenore" from the room with the aerogarden, unless i want water everywhere as she did last time.
larry