If you had a choice between?

[clamlvr]

If you hade a choice what would you pick a PFO HQI or a sunlight supply HQI balast or the E-Balast to run a 400 Radium :eek3:

[Steve]

Probably an eballast since that one is electronic. Also, the HQI ballasts will burn the bulbs brighter, but they will also burn out sooner. I would rather have the bulbs last longer, but it is personal preference. However, I would pick a ballast that you did not list. This is the ballast Sunlight Supply will recommend to run the Radium 400. http://oceanencounter.com/Merchant2/...tegory_Code=SL

[clamlvr]

what is the diffrance between an HQI and a pulse satrt balast, all the post I have read gave me the impresion that the HQI balast is the way to go for a radium

[Steve]

The HQI will definitley drive the bulbs brighter and more white. That is because they are actually overdriving the bulbs. There is speculation that this will cause the bulb to have a shorter lifespan, but right now that is all it seems to be - speculation. Nobody has done any scientific tests on the longevity of the bulbs with the different ballasts. I would rather see the bulb have more of a blue hue myself, so I would pick a Eballast or the recommended ballast that Sunlight Supply suggests. You can always email Perry at Sunlight Supply for his explanation.

[Papa Doug]

I ran the Sunlight Supply pulse start on my pair of 400w Radiums. Not as bright as HQI pics, but, very nice IMO. It was easily the nicest light over my tanks ever.