Par

[sstraub5150]

What is PAR? What is its importance and how does one measure it?

Thanks

 

[glxtrix]

photosythentically available radiation. Its important to corals because certain corals need a higher par to live. Lights give off this energy and corals use that energy to create food to live. Par is measured by a par meter (quantum meter) the club has one. Typically the higher the par the better for sps. Softies can live with lower par values because a lot of them don't require light to survive.....many are filter feeders.

 

[sstraub5150]

thanks for the response. My question is whats the ideal and is what I have enough?

 

[skriz]

what do you have? There is no "ideal" par value.

 

[sstraub5150]

24 gallon cube with a 150 watt halide with a 14k bulb. My tank is the second listed in the member tanks forum.

 

[sstraub5150]

I have a spare 70 watt halide that I could put on as well if its not enough light.

 

[skriz]

yep, it's enough!

 

[skriz]

don't waste your time with the 70 watt crap. upgrade the bulb if you want "more"

 

[sstraub5150]

Skriz;195915 wrote: don't waste your time with the 70 watt crap. upgrade the bulb if you want "more"

Its a 150 watt sunpod, any upgrade suggestions?

 

[mufret]

Take a look at some of the "better" bulbs that are available.

 

[sstraub5150]

mufret;195919 wrote: Take a look at some of the "better" bulbs that are available.

Any recomendations?

 

[skriz]

I'm not sure which bulbs are available in the 150w range, but the 10k bulbs will offer much more par than what you are currently getting.

For example, the xm 10k will put out 50% more par than the aquaconnect 14k (150w DE bulbs). The 10k colour may be different than a 14k bulb though. ALthough, looking at your pics, it may not be any difference. Also, your bulb may not be putting out as much par as the ac bulb, so the par difference may be much greater (100%).

 

[sstraub5150]

Is this a good one:

 

[skriz]

yes! the xm 10k is an excellent bulb for par.

 

[skriz]

if you're pics are accurate, the xm 10k will look similar, but will have double the par.

 

[sstraub5150]

Skriz;195936 wrote: if you're pics are accurate, the xm 10k will look similar, but will have double the par.

I'm gonna stop by aquabuys tommarrow and pick one up. Thank you for all your help.:up:

 

[sstraub5150]

I put a 150 watt 20k Radium in it. NIGHT AND DAY!!!!! Thanks to Sam at Aquabuys. It should bring out the blues in my acros more.

 

[dannybradley]

I think I need to define PAR a little better for this thread.

PAR is Photosynthetically Active Radiation. It's a measurement of light useful for photosynthesis. Specifically it's a measurement of the amount of photons that strike the sensor converted to umol x m^2 x second of wavelengths from 400 to 700 nm.

A Quantum Meter is used to measure PAR. It can be useful in determining coral placement and if infact that coral can even be kept under your current conditions. It can also determine bulb decay by the user taking measurements periodically to determine that the PAR level has dropped to a point where the bulb require replacing.

It becomes quite difficult to determine what coral needs what specific amount of PAR. Dana Riddle is currently doing experiments with coral color protein to define what specific corals need in terms of PAR values. If you'd like to learn more, I suggest searching for some of his work online.

 

[sammy33]

Check this thread as well for more details:
http://www.atlantareefclub.org/forums/showthread.php?t=4695">Fun with the PAR meter</a>

:)

 

[sstraub5150]

dawgdude;196188 wrote: Yup, radiums are great bulbs. I might have to try one of those sometime.

To be honest it looks like a 14k that came in the light stock but much brighter. I can't run actinics in my setup so i'm very happy with it.