Subject: Aquarium bulb
Hi, would you be able to tell me what the light blue powder is in an
PennPlax or Hagen Gro bulb. They are used for plant growth in aquariums.
I think the blue color blocks out the yellow light that plants do not
like. It is not fluorescent, it is incandescent, about 5 inches cigar
shaped, screw in type.? Unfortunately I broke one on the floor the other
day, swept it up and then vaccummed the tiny bits. Because it was
incandescent I didn't think about Mercury but I began to wonder? What is
this powder? Can you help? Thanks Doug
