Black lights are the only incandescent light bulbs that are as close to the 730nm (only) spectrum you can get.

Incandescent black lights are actually a form of Standard Outdoor Darkness (SOD). So yes they can be used as a flowering night light.. BUT inc black lights (only) during your 12/12 flowering darkness will cause unwanted stretch for sure. After the stretch phase is over however then black lights (only) can be used for some SPEED, but not very efficiently IMO...Inc black lights have a time factor of aprox .9 and are very fast as far as spectrums go because they give off mostly 730nm.

IMO you need to be careful about adding speed to your normal 12/12 flowering (dark time)..To much speed will cause your lighting schedule to go from a 12/12 to a 10/14 type of flowering in a heartbeat especially if your using HID. So a little goes a long way..It's ok to do it at the end of a normal 12/12 type of flower, maybe for the last two or three weeks. But again it's not the most efficient way of adding speed to the flowering time IMO unless your doing a 24/12 type of flowering. For every hour of black lights (only) used during your normal flowering (dark time) you will get aprox 1.1 hours worth of SID darkness. So using black lights for let's say 5 hours will give you aprox 5.5 hours of SID. And using them for 12 hours will give you aprox 13.3 hours of SID darkness. So ya they work in a normal 12/12 flower if you know what your doing with them... Hope that helps ya...

The funny thing about green inc's is.. They will make your girls come out of flowering unless you use a filter with them. The only spectrums that work for the dark phase of a flowering cycle is 530nm and above. If I'm not mistaken green inc's fall below this range. So they can be used but I think you will need to use a filter with them.. Again not worth it..

Is that the answer you were looking for or no..:thumbsup: