Where did the blue go in my 20K MH lamp from 17 years ago?

mandarin417 · 09/23/2015, 07:42 AM

I had a choice then – go with the tried and true VHO lamps or try the new power compacts or MH lamps. I chose the 400W Ushio 6500. I could remember most of the coral names then since there were only 10 or so available. I wanted to venture out and try an acropora coral. No variety names at the fish store – just an acropora.

The 6500 grew everything well in its yellow cast light. Someone told me to add a 20K lamp to give my livestock better coloration so I added another 400W lamp over the tank. Wow what great colors with the 6500 and 20K running at the same time. I used the 20K as the first lamp to light up and the last to go off. Just MH on the tank then – no VHO’s or power compacts.

The 20K cast a very deep blue, almost violet color in the tank. It was like a super actinic experience.

Now I am back into reef keeping after a 15 year break. Powered up my Radium 20K lamps a few months ago. Where did the intense blue go? I get a very nice bright white but nothing like the blue I had back then? Running these on switchable electronic ballast with 400 and 400 HQI options.

ca1ore · 09/23/2015, 08:27 AM

Different ballasts can drive bulbs quite differently.

SPotter · 09/23/2015, 08:29 AM

are you running on 400 or 400hqi setting?

mandarin417 · 09/23/2015, 08:45 AM

Hi Steve - I have run both settings and to be honest - don't see any different in the light produced.

As I recall, the ballast I used 17 years ago was a 400W PFO ballast. My tank ran very very very blue with that ballast and 20K lamp.

The 20K I am running on the electronic ballast produces a nice white light. Just not that intense blue of the one I ran back in the old days.

SPotter · 09/23/2015, 08:57 AM

Quote:

Originally Posted by mandarin417

Hi Steve - I have run both settings and to be honest - don't see any different in the light produced.

As I recall, the ballast I used 17 years ago was a 400W PFO ballast. My tank ran very very very blue with that ballast and 20K lamp.

The 20K I am running on the electronic ballast produces a nice white light. Just not that intense blue of the one I ran back in the old days.

Im running them with the Galaxy ballast, have tried both settings as well and don't notice a difference but agree that its more white than I expected it to be. I have thought about buying the Hamilton ballasts and see how they look.

alton · 09/23/2015, 09:40 AM

Radium 20K is closer to 14K. If you have a Phoenix 14K SE and a Radium 20 K they look the same.

mandarin417 · 09/23/2015, 09:56 AM

Maybe I wasn't running 20K Radiums back then. Maybe they were Ushio 20k 400W or some other brand.

09/23/2015, 07:42 AM	#1
mandarin417 Registered Member Join Date: Apr 2014 Posts: 127	Where did the blue go in my 20K MH lamp from 17 years ago? I had a choice then – go with the tried and true VHO lamps or try the new power compacts or MH lamps. I chose the 400W Ushio 6500. I could remember most of the coral names then since there were only 10 or so available. I wanted to venture out and try an acropora coral. No variety names at the fish store – just an acropora. The 6500 grew everything well in its yellow cast light. Someone told me to add a 20K lamp to give my livestock better coloration so I added another 400W lamp over the tank. Wow what great colors with the 6500 and 20K running at the same time. I used the 20K as the first lamp to light up and the last to go off. Just MH on the tank then – no VHO’s or power compacts. The 20K cast a very deep blue, almost violet color in the tank. It was like a super actinic experience. Now I am back into reef keeping after a 15 year break. Powered up my Radium 20K lamps a few months ago. Where did the intense blue go? I get a very nice bright white but nothing like the blue I had back then? Running these on switchable electronic ballast with 400 and 400 HQI options.

09/23/2015, 08:27 AM	#2
ca1ore Grizzled & Cynical Join Date: Apr 2006 Location: Stamford, CT Posts: 17,319	Different ballasts can drive bulbs quite differently. __________________ Simon Got back into the hobby ..... planned to keep it simple ..... yeah, right ..... clearly I need a new plan! Pet peeve: anemones host clowns; clowns do not host anemones! Current Tank Info: 450 Reef; 120 refugium; 60 Frag Tank, 30 Introduction tank; multiple QTs

09/23/2015, 08:29 AM	#3
SPotter Registered Member Join Date: Jun 2010 Location: Mt. Pleasant, SC Posts: 5,691	are you running on 400 or 400hqi setting? __________________ Steve Am I really doing all of this for a fish tank?????? Current Tank Info: 360g Envision Acrylic Tank, Closed Loops, Vectra L1's, MP40QD's, 400w Radiums, Regal 300ext, Dastaco Ext3 CaRx, Controlled by GHL Profilux

09/23/2015, 08:45 AM	#4
mandarin417 Registered Member Join Date: Apr 2014 Posts: 127	Hi Steve - I have run both settings and to be honest - don't see any different in the light produced. As I recall, the ballast I used 17 years ago was a 400W PFO ballast. My tank ran very very very blue with that ballast and 20K lamp. The 20K I am running on the electronic ballast produces a nice white light. Just not that intense blue of the one I ran back in the old days.

09/23/2015, 09:40 AM	#6
alton Registered Member Join Date: Jan 2005 Location: Zuehl, Texas Posts: 4,460	Radium 20K is closer to 14K. If you have a Phoenix 14K SE and a Radium 20 K they look the same.

09/23/2015, 09:56 AM	#7
mandarin417 Registered Member Join Date: Apr 2014 Posts: 127	Maybe I wasn't running 20K Radiums back then. Maybe they were Ushio 20k 400W or some other brand.