Can some one explain PAR to me?

[jgreenway]

I am going t get a Hamilton hood fixture for my 36Lx18Wx21D tank that has 2-250W HQI and 2-96W PC. I plan on mounting the light 14" above the tank with brackets off the wall the tank is going to have an open top. Does that sound about right to you guys or is their a better way.

 

[Len]

PAR = photosynthetically available radiation. It's just a term for the quantity of light within 400 and 700nm wavelengths.

Your lights sound great.

 

[jgreenway]

You don’t think it's too much what about heat. If it is could I just replace the 250W with 150W and use the same fixture and ballast?

 

[Unarce]

The 150W bulbs are slightly shorter than the 250W bulbs, so you'll need a different fixture and I think a different ballast.

2 250's won't be too much. Personally, I'd skip the PC's and just use 2 20K bulbs. You'll be getting intense enough light with 250W DE (HQI's), but at a more natural spectrum.

Have fun! :wink:

 

[danmhippo]

Oh, is that what it meant? I thought it was a golf term used wrong.........

 

[Len]

Fan cool it and you should be fine. But of course this depends on where you live. If you use A/C, this isn't an issue (often it's cheaper to run A/C versus a chiller .... and people get cooled too )

 

[jgreenway]

Thanks for the help I will probably get the fixture I might not run the pc but at least I will have the option. I plan on using them mainly so I don’t shock the system by going from no light to 2-250W. It's hard to find a light that has 2-MH in a 36" fixture if someone knows of another manufacture of one instead of Hamilton let me know so I can compare prices the Hamilton is expensive but I figured it is one of the most important parts of the happy reef tank