Planted Tank VIP
Join Date: Jul 2002
Location: Winston-Salem, NC
The 10-14 month lifespan generally applies in relation to color spectral shift, not output intensity. A bulb will produce a fairly high initial lux intensity (say, 4800 lumens, for a GE 9325K 55 watt PC bulb) and then quickly drop off to near its average luminosity (4080 lumens, for the same bulb) after only a hundred hours of use or so. The bulb will stay near its average luminosity for its lifespan (generally 10,000 hours over 2 years with a 12 hour photoperiod.)
All that being said, there is no official study of how long ODNO bulbs last. I've noticed some blackening of the bulb ends after about a year of use, at whic time a fresh bulb will show considerably improved output.
- Sam P -
plantedtanker in limbo - all tanks currently in storage