For those interested in MH bulbs

[cilyjr]

Wow let's get this back on track. Here is an article from 2007 that I have looked at in the past that gives a bunch of par readings from se 250 w bulbs.
Thing is its from 2007 so many of the bulbs are no longer available that said mh tech hasn't changed much in 10 years. Both the radium and the Hamilton 14k bulb are tested

http://reefkeeping.com/issues/2007-04/jb/index.php

 

[cilyjr]

Also I cant seem to find it but there was an article several years ago by sanjay joshi that found the Hamilton 14k spectral chart very similar to the radium. Which by the way is not mentioned as a 20k by the manufacturer. They call it the hrt aquastarblue

 

[mcarroll]

Also I cant seem to find it but there was an article several years ago by sanjay joshi that found the Hamilton 14k spectral chart very similar to the radium. Which by the way is not mentioned as a 20k by the manufacturer. They call it the hrt aquastarblue

I think they didn't used to, but they do now (the whole site has been reorg'd a couple of times since I bookmarked my 150DE's all those moons ago.....halide is now in a category like "other lighting" even for them):
https://www.radium.de/en/products/metal-halide-lamp-quartz-burner-hri-t-250w230be40

• Lamp nominal wattage250 W
• Luminous flux7500 lm
• Colour temperature20000 K
• Mean service life4000 h
• dimmablenein
• BaseE40
• Lamp shapeTube, one base

 

[mcarroll]

Just more good nerd Radium details....

Electric Parameters
Lamp nominal wattage250 W
Rated wattage270.0 W
Mains voltage230 V
Ignition voltage4.0 up to 5.0
Lamps nominal current3 A
Nominal choke current3 A
Running up current max.190%
Compensation capacitor for 50Hz operation32 µF
Energy Consumption kWh/1000h297
FuseDaelay-action min. double nominal current

 

[maroun.c]

Any experience with Ushio?
I run DE and we didnt get radiums anyway here. And the fact It needed special ballasts kept me away. Ive been running ushio and Phoenix since 1998 and always had great colors and growth, also tried reflux and gieseman which I didn't really like.

 

[mcarroll]

I think I remember Ushio being on a list as also taking the same ballast as Radium. Need to find that reference tho...

And Radium's didn't "need" the right ballast, but they'd run differently otherwise.

From memory...

The 150 and 250 would run "cooler" on a regular ballast – just at their nominal wattage – which I think would make them run very blue.

On the right ballast they're run closer to 180 and 270 watts and the color was more of a crisp white-blue.

The 400 watt bulbs were a little different since their nominal rating was only 360 watts....400 watts was overdriving them similarly to the 180 and 270 watts for the other bulbs.

I really liked the overdriven Radium look. Wonder what difference in K-value between an overdriven vs an underdriven Radium is?

 

[cilyjr]

The 150 and 250 would run "cooler" on a regular ballast – just at their nominal wattage – which I think would make them run very blue.

On the right ballast they're run closer to 180 and 270 watts and the color was more of a crisp white-blue.

This is 100% correct. I've messed with both 250se and 400se bulbs and have ballasts that will run the bulbs at both 250w and overdrive (10% more) which runs them at 275w. With the 400 running at 400 and 440
The 250w running at base is very blue (likely close to 20k). And the overdrive likely closer to 14 or 15k. Again I wish I could find the sanjay joshi article from maybe 6 years ago going over this. But the spectral chart comparing the Hamilton running at 250 was very similar to the radium a quarter at 275 watts.

I have a bunch of Bulk Reef Supply points and will be getting a Hamilton bulb to look at the difference and and thinking will run a full set of them next year. I also called Hamilton curious about a possibility of discontinuing these bulbs. He assured me that they are going to be in production for a while due to the fact that many other companies are discontinuing their bulbs and many people are switching back to metal halide. He said they're actually seeing an uptick in the Hamilton 15k bulb sales