budleydoright
Member
The bulb is most definitely not "sealed" in the fresca. I have to vacuum gnats out of the inside all the time. The only thing "sealed" is the space between the 2 tubes. The inner space is basically open. There are end covers, but they have weep holes in case of leaks or condensation. They also have notches for the water lines. I assure you, If I ran my water below the dewpoint, the insides of the tubes would sweat on a humid day.
Too hot and dry on the insides of them when they're on but when they're off no doubt plus cold condensation dripping on plants at night is an invite for PM.