[SSLEWTER]

I Just Ordered Some New Lights For My 20 Gallon Long Tank
My Old Lights Were
2- 96 Watt Quad Pc
1- 65 Watt Actinic Pc
My New One Will Be
1- 175 Watt Metal Halide Se 14k
And 2 - 65 Watt Actinic (or 10k) Pc
If I Can Squeeze 3 In I Will
All Lights Will Be 3-4 Inches Off The Water

My Question Is Will This Be A Large Enough Boost So I Can Grow Some Acros? 2nd Should I Go With The Extra Actinic Or The 10k Pc ?
I WOULD LIKE TO HAVE NICE COLOR AND GLOW BUT ALSO HAVE SOME GROWTH

Thanks For Your Comments

[Reefland]

In a 20 that will be fine for growing some sps corals.

[charlie]

If it was me, I would go with the extra actinic, but I like the blue!!!!

If you are wanting to try some acros, go slow, and see if they will color up under the 175W. JMHO
I know for sure you could get some LPS going in there.

[SSLEWTER]

I Believe I Am Sold On The 14k Mh I Will Have 2 - 55/65 Pc Lights Poss 3 Not Sure If I Should Have All Actinic ( Ie Too Blue ) I Would Like Color To Glow And Pop But Not Look Wacky Along With Growth
Thanks

[charlie]

I think you will be happy with 2 of them, and 2 PC for supplementation, but I also believe you are going to have some heat issues!!!!! Are you going to be running a chiller. Have you looked into T5 lighting, they run much cooler and also will provide what you want for sps. Do some searching around on here on T5 lites. JMHO

[SSLEWTER]

Thanks
No Chiller ($$$) But House Stays Pretty Cool I Do Have And Plan On A Couple Of Small Fans

So Go With 2 Actinic For The Supps? I Can Do That Thanks

[SSLEWTER]

OK
I SET UP MY 1--175 WATT METAL HALIDE 14k BULB AND I WAS ABLE TO FIT IN 3 PC LIGHTS 1 --IS A 65 WATT ACTINIC AND 2 --ARE 7100K BLUE LIGHTS
THESE 7100K BLUE LIGHTS ARE BRIGHTER THAN THE ACTINIC AND REALLY MAKE THE COLORS POP

I HAVE READ THAT CORALS GROW BEST IN SOMETHING LIKE 6500K LIGHT WHICH IS SUPPOSE TO BE A YELLOWISH AND GROWTH IS SLOWED UNDER 20K SO HOW WILL THEY DO WITH THESE 7100K SINCE THEY ARE BLUE AND MY 14K LIGHT IS ALSO MORE BLUE THAN 10K? ALSO WHAT K IS NORMAL ACTINIC? I LOVE THIS NEW GLOW

I GUESS I AM GETTING CONFUSED BY THE BLUE PART IN ALL THIS MORE BLUE (20K) SLOWS GROWTH BUT 7100 IS MORE BLUE BUT CLOSER TO 6500(YELLOW) I DONT KNOW ???

I LOVE THE COLOR JUST TRYING TO UNDERSTAND

[Ninong]

The 7100K number for actinic compact fluorescents is simply a number they pulled from thin air. It means absolutely nothing. In general, it's a safe bet to assume that the so-called 7100K PC actinics are predominately 450-460 nm. The so-called "true" actinics are usually 420 nm.

There is no "K" for "normal actinics." It's impossible to assign a Kelvin rating to a lamp that is basically monochromatic. That's why Radium advertises their blue metal halide lamps as simply "blau," German for blue, instead of 20,000K. We call them 20,000K but Radium calls them "blau."

You may or may not realize that your 14,000K lamp may or may not be anywhere close to an actual 14,000K. Not only that, it may or may not produce more PAR than a similar wattage 20,000K lamp, which is probably a surprise to most people. It almost certainly produces a lot less PAR than most 10,000K lamps. (Read this thread. We discovered that the Radium 150w 20,000K HQI DE lamp has a lot more PAR than the 14,000K 150w HQI DE lamp he was previously using.)

There is no way to answer your questions in a few simple paragraphs. I suggest you do some research on light requirements if you want a better understanding of this topic. You could start with Sanjay's article on Photosynthesis and Photoadaptation.



P.S. -- More trivia: Some 14,000K lamps are bluer in appearance than some 20,000K lamps. Iwasaki sells a 150w 50,000K metal halide medium base lamp that is not as blue as most 20,000K lamps. In addition, you need to know that the ballast can make a big difference with metal halide lamps. Some 20,000K lamps are much bluer on some ballasts compared to other ballasts.

I have absolutely no idea how Iwasaki arrived at the 50,000K designation for that lamp. In actual appearance, it looks more like a bluish 10,000K lamp.

[Ninong]

You may find this article helpful in understanding some of the basic terms.

[SSLEWTER]

Thanks Ninong
You Always Have The Info Needed
I Am Pretty Happy With The Color I Am Getting Right Now You Suggest Going With A 10k For More Par I Will Try That On My Next Bulb That Would Provide More Coral Growth
I Am Running My Pc Blues About 10 Hours A Day With My 175 On For 30 Mins And Off For 15 Mins For The Same 10 Hours A Day I Dont Want To Burn Or Over Heat The Tank Only Had Them In A Few Days

Also (peltier) Cooling I Have Been Reading About This Ice Prob Looks Like It Is The Same Thing $$$ Mini 1-6 Can Coolers (refrigerators) Seem To Have Peltier Cooling In Them
Anyone Have A Diy For A Small Chiller? It Looks Like A Fun Thing To Tinker With Thanks