What is PAR

[mr9iron]

What is par? And how does this apply to a 175 watt 10000k german metal halide bulb. Is this adequate for my tank. Its a 39 gal oceanic, several softies,several sps, 2 fish,many other inverts. Photo period is 11 hrs a day. No other supplementation.

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Air goes in and out, blood goes round and round. Anything different is a bad thing......

[PerryinCA]

PAR= Photosynthetic Available radiation.

Its directly correlated to the EMR emmitance frequency a given light, or discharge tube gives off. The frequency (and wavelength) of electromagnetic radiation at visible levels (within the light spectrum) determines the color.

The chloroplasts, and photosynthetic accessory pigments are more efficient with certain colors of light. Generally PAR refers to the total spectrum photosynthetic animals can utilize to produce glucose (the byproduct of photosynthesis).

Now as for your tank- Lighting is normally measured for PAR in tests with the proper equipment. I am not sure of the PAR of your 175 watt lamp as it can very with manufacturer and type of ballast used.

Generally it seems that what you have is OK. Personally I feel that 175 is not enough light for SPS. Most I have seen will usually brown out, and growth will slow extremely. SPS do best with 250 EYE, HQI or better. Now thats not to say that there are likely people who have had good luck with the 175w, but IME 250 is far better, and likely far from enough. Just be sure to have yours high in the tank.

-Perry



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Some call it evolution,
And others call it God.
Each In His Own Tongue (1908)
William Herbert Carruth 1859-1924

[NCF]

What do you mean by 250 EYE???


[img]/ubb/uhoh3.gif[/img]

[Ninong]

Originally posted by NCF:
What do you mean by 250 EYE???


[img]/ubb/uhoh3.gif[/img]

He means 250w 6500K Iwasaki metal halide lamps with mogul base.

[Ninong]

EYE is the name of the manufacturer, Iwasaki Corporation. http://www.eye.co.jp/

[reefland]

To build a little furhter, the HQI and Iwasaki lamps are powered differently. So on the market you will find a standard ballast, EYE ballast and in some instances HQI ballasts.

PFO has all three ballasts, IceCap only has 2; 1 is for the Iwasaki specifically.

[NCF]

Maybe I sould open a new thread called acronims... What is PFO ???

[Ninong]

PFO = PFO Lighting, Inc.
http://www.pfolighting.com/

Ninong [img]/ubb/biggrin.gif[/img]

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Irrational Exuberance!

[NCF]

I still don't see the connection between EYE and those lamps...

[wgscott]

The purple curve is what the eye sees. The blue curve is what a photosynthetic organism finds useful. Visible light is measured in LUX, and photosynthetically useful light is measured in PAR.

[This message has been edited by wgscott (edited 03-02-2001).]

[Ltspd]

Wgscott, Nice graph. What are the mesurments for on the vertical side. I assume the bottom is color wave in Nanometers. Is the side intestity?

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Paul C
Things should be made as simple as possible, but not any simpler.
Einstein

[wgscott]

relative quantum yield.

[Reef Engineer]

Damn - all this time I though PAR meant that you made it in the hole in the predetermined number of strokes [img]/ubb/biggrin.gif[/img] Guess I was wrong!

Randy

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Come meet the gang!
http://www.homestead.com/reefengineer/homepage.html

[Ninong]

Damn, Randy, didn't you do this the last time someone asked this question? [img]/ubb/lol.gif[/img][img]/ubb/lol.gif[/img][img]/ubb/lol.gif[/img]

Ninong [img]/ubb/biggrin.gif[/img]

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Irrational Exuberance!

[JerseyReef]

Randy,
Hows the tank these days? Did it fully recover with your bout of RTN? I would love to visit your web site, but it kills my cable modem!!!


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Mike
jerseyreef@home.com

[Reef Engineer]

Ninong,
What!?! You accusing me of using old material!?! [img]/ubb/biggrin.gif[/img]

Mike,
Sorry hombre! I'm working on getting a better software package that'll allow me to make the files even smaller so that it isn't so bad. You should have seen it BEFORE I started compressing them! [img]/ubb/biggrin.gif[/img] The RTN is ancient history - thank God! No relapse that I can see and all are now doing well. I plan on updating things soon on the site since MANY things have changed - most for the better! I've replaced several brown corals with purples, blues, yellows & greens - much more appealing to the eye, IMO!

Randy

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Come meet the gang!
http://www.homestead.com/reefengineer/homepage.html

[Skipper]

Hey, Reef Engineer. You don't necessarily need any software to make your pictures load faster. Go to this site and it will compress them for you, making your load times much more tolerable. http://www.webreference.com/services/graphics/jw/
I had many images that were over 60 seconds to load until I went to this wizard and reduced the load time to 3 or 4 seconds. HTH




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Skipper's Reef

[Reef Engineer]

Skipper,

Thanks a bunch, hombre! I'll go check them out later tonight. I have about 150 shots that I need to compress so I'll be a busy beaver. I've taken new shots of the tank since the tank has really changed a bunch since the majority of my shots were taken, Most of them are at least a year old - a lot changes in the tank in that type of time!

Thanks again,

Randy

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Come meet the gang!
http://www.homestead.com/reefengineer/homepage.html