Steve Tyree's chat the other night

[Delphinus]

If one was considering going a blue 150W halide, it seems to me the choices would be the DE/HQI Radium 20k, or the Iwasaki Aqua (aka "50k").

According to this analysis the Iwasaki Aqua seems to show a spike at 450nm.

I can't find a similar spectral analysis for the 150W Radium. Does anyone know of one they can point me to?

I wonder which one of those two is the "more blue."

(Can you tell, I have a 150W ballast? :D I still haven't decided what to do with it. Supposedly it can do both the DE's and the mogul's though.. so hence the choice between the two bulbs for me.)

..

So DJ88, have you figured out yet which blue bulb you're leaning towards (the Sunburst 250W or the Radiums)?

It seems to me, that the 400W Radiums, if used on the 430 HPS ballast with starter (ooops pardon me, I mean the "HQI" ballast) or the Bluelines, are good enough to be used on their own, with a PPFD almost equivalent to 250W Iwasakis. Supposedly, if used on a conventional 400W MH ballast, the bulbs are just "blue" and probably should only be supplemental (except that 400W is a lot of juice for a "supplement").

Don't know much about the Sunbursts. Or the 14k's (whoever makes those). I used Hamilton-stamped 14's (175W) over my tank for the first year of me using halides, and I didn't much care for them at the time. They were spent at 6 months, on a 6-hour photoperiod, and at that point seemed to be only good for growing hair algae and cyano. The corals never did much under them (although they sure "looked" good, but the stoneys had very little, if any, growth during that time). So definitely not good enough as the primary light source, but maybe not bad as a supplement to the Iwasaki's...