The Par Meter Thread

[Deuce67]

A par meter is now available for club member use. The meter will alternate between Colorado Springs and Pueblo. Todd(racer69) will hold on to it when it is in Pueblo and Chris(reefkoi) in Colorado Springs. The meter will exchange hands after every meeting. The meter consist of the meter itself with a corded sensor, a protective cap for the sensor and an instruction manual. If borrowed, please share to us a report or a brief summary of your readings.

The info will consist of:

1) Type of light (MH, T5, PC, VHO etc)
2) Type of ballast. (Normally for MH users. Electronic or magnetic)
3) Wattage of lamp
4) Age of lamp
5) Kelvin of lamp (10K, 14K, 20K etc)
6 Type of reflector (Lumenarc, spider, flat polish, none etc)

Take a recent pic of your tank and write down your findings on various location of the tank. You can use Microsoft paint to put in the numbers on your pic.

Please try not to get the meter itself wet. Only the sensor is waterproof. The meter itself is not.

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Enjoy! Just another benefit of being a SCMAS member!

[Deuce67]

Ill start

1) MH
2) Electronic Coralvue
3) 400W
4) 1.5 weeks old
5) 10K
6) Lumenarc minis

3" below the water line, directly under the bulb, I was getting a reading of 1650. All pumps were shut off during the test.


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Not sure what these readings means so far. Ill try to find out or have someone who has experience chime in. Anyways, i also tested my 110W VHO. The lamp is only 2 weeks old. 2" away from the lamp, I was getting 180.

[The Grim Reefer]

It's important to try to keep the sensor as level as possible. You can use about anything flat which can be screwed into the bottom of the sensor to keep it flat on the sand.

As far as the readings go Sanjay Joshi suggests having a minimum PAR of 150 at the sandbed for a full SPS tanks. As far as the different readings around the tank it's kinda hard to say what you should be looking for as far as specific numbers for different corals. Do a Google on Dana Riddle and photo inhabition and you should come up with an article but they are just scratching the surface as far as how much light a coral can handle.

Remember to do the math on the readings you get. If the meter is a electric light calibration you add 2% for halide readings. If it has a sunlight calibration you subtract 10% for fluorescent lamps and 8% for Halides. Couldn't tell you why, it's all in the instructions.

[lfduty]

Thanks Grim for the inputWe all will be calling you from time to time I know i will I SUCK at math HA just like my spelling

[The Grim Reefer]

Another thing, be careful not to tug on the cable coming out of the meter. They have improved how it is connected but it still shouldn't be tugged on as in, if you knock the meter off a table let it drop rather than catch it by the cable.

[Deuce67]

Thanks for chiming in Grim. I guess Im doing well with a read of 250 down on the sandbed. I cant seem to find any info on photo inhibition by Riddle thou.

[The Grim Reefer]

Here's a bunch of reading on the subject, I dont think I added any duplicates.


http://www.advancedaquarist.com/2007/3/aafeature1
http://www.athiel.com/aquatic/riddle3.htm
http://www.reefs.org/library/talklog...le_090599.html
http://www.athiel.com/lib4/par1.htm
http://www.aquarium-design.com/reef/lightingbasics.html
http://www.advancedaquarist.com/2002/2/aafeature

[reefkoi]

OK I took some measurement on the 600 gallon tank
30" water depth
10" from water to bulbs
1000 watt Helios 20K bulbs
1000 watt PFO ballast
1 month old.
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I took some measurements in the 10 gallon nano also
250 watt HQI
AB 10K bulb
Icecap elec. ballast
6 month old bulb

3" above water 1600 par 4" below bulb
water surface 1000 par 7" below bulb
3" below water 630 Par 10" below bulb
bottom of tank 290 Par. 17" below bulb

now comparing that to the 600 we get

1" below water 1950 par 11" below bulb
4" below water 1600 par 14" below bulb
12" below water 1000 par 22" below bulb
18" below water 400 par 28" below bulb
on the sand bulb center 400 par 36" below bulb
on the sand offset from center 200 par 36' below bulb

So in conclusion at 10" below bulb we have 3 times more light with a 1K watt versus a 250
at 17" there is almost 4 times as much light
I cannot check any deeper than that since the 10 is a shallow little tank.

[Deuce67]

Man, Mt Fuji is definitely getting some serious par.

[reefkoi]

LOl yes it is. what is interesting is that I am getting similiar numbers as you down lower but you have 10K and I have 20K.
That was my goal with these is to get 400 watt 10K numbers with a 20K bulb.
So in a sense at midtank and lower the corals see the same amount of light as a 400 w 10K but they look bluer.
It's a good thing my rockwork isn't built up so high that i have to place corals up high.
I need some more hyacinths to place on Mt. Fuki since that's the only coral that will live there most likely LOL
Chris

[aquaman2000]

WOW!!!!!

The par on the 2 1K's on the 225 was incredible! After seeing the 1K's in action..... there is no othe system I will concider on large SPS tanks.

I took the PAR meter into the sun for a base line and read around 1850. I then put it under my 400 Watt XM 15K SE bulbs 3 months old and the par read about the same as sun at around 4 inches of air. I'm thinking sweet!!!!! then I put it in the water and at 1/2 inch it droped down to 800!!! 1/2 inch of water and I lost 1000 PAR. Then at 8 inches it droped to 320 and on the bottom at 20 inches down to 200.

So I tested Chris' old 250 DE luminarc stelths with pheonix 14K bulbs around 3 months old ( I think) anyway they read about the same as the 400's at 4 inches of air 1850 or so any higher and the meter maxes out. Now here I am surprised, at 1/2 inch the 250 DE is 1150, I had to check both tanks again, 1150 at 1/2 inch. At 8 inches the pAR is at 550, at 20 inches it is at 130 and on the bottom of the 180 gallon, it is 100. I can't wait to get the 400Watt bulbs into the luminarc III's to see what kind of differance it will make.

Russ, Forget the 400's....... join the 1K club!!!

[Deuce67]

So, what was the reading on the 225? Cant use the par meter for sunlight. Its calibrated for electrical lights. The readings you got for the 15Ks isnt too bad at all for the reflectors you got.

[calvin415]

I believe we were at 400 on the sand, and that's with the reflector a foot off the tank, bulb was 15" off the tank... Don't remember the other numbers cause Chris was reading the meter while I was trying to get the sensor in the tank...

[reefkoi]

I think he was at 1400 or 1600 just into the water and 700 was the average reading when eric was moving it around. 400 on the sand.
I love this new tool, I think now that we have some baslines it will be great to look at the 6 month mark and even 1 year mark to see what the bulbs put out as they get older.

[Deuce67]

Who has the meter? Can I borrow it?

[reefkoi]

Scott has it, just go down there and grab it.

[racer69]

Are we going to make sure the par meter is at this meeting? I might be taking it down to Pueblo and take some readings.

[Deuce67]

Its already over at Tims house Todd.

[racer69]

Great.