Geisseman/ATI equivalent

[authentic]

Which geisseman bulb is equivalent to ATI blue plus?

 

[reefwiser]

Geisemann Actinic+

 

[Bpb]

That's the old D&D Giesemann bulb. The new Giesemann Powerchrome bulb closest to the ATI Blue+ is the Giesemann Actinic Blue. It's got nearly an identical spectral graph. Maybe just a touch deeper in the blue region with less of a green spike. It's a little darker blue, not quite as bright (not necessarily weaker, just deeper down the blue spectrum which appears dimmer, and some would say more visually appealing.