400Watt 20K Radiums

**Mike** · 03-01-2010, 11:46 AM

Totally love the bulbs esp on Lumatek ballast. What I realized over the last week was the tank was looking dimmer so today I changed the bulbs (replaced with Radiums) and it is so much brighter. From what I am seeing It looks like on the Lumateks the limit may be 6-7 months before the light-output starts to decrease. This may be the last set I have to change though (designing LED Array).

The thing that I noticed with the corals was they were starting to fade just a bit (esp blue corals not directly under the bulb). The corals under the new 20K (250's) have not had that issue. Which leads me to think that this was a result of a color shift perhaps as well as a decrease in output.

**dejavu** · 03-01-2010, 09:18 PM

There nice bulbs, I have been running them for awhile now.

**Hopkins** · 03-01-2010, 09:22 PM

Ouch, 6-7 months! That is going to get expensive.

**Mike** · 03-01-2010, 09:24 PM

That is the reason I am going to start moving into the high powered LED's

**dejavu** · 03-01-2010, 09:26 PM

They will last alot longer if you don't over drive them. I run them on a true 400 watt ballast and have gotten well over a yr out of them with descent par values still.

**Mike** · 03-01-2010, 11:16 PM

I am running on the Lumateks and they are supposed to start the bulbs easily (without power surges) and adjust he current to optimize performance. That said I still love the bulbs.

**rxpharm** · 05-31-2010, 01:42 PM

Ran 400 watt 20K radiums for a couple of years and found I could get maybe 8 months tops before they turned very yellow and had visible decrease in output. I am running XMs for a while now and see no change in color or intensity at 14+ months.