PAR values for par38 LEDS

[zygote2k]

Beeker from RC had this to say-

 

Location: cincinnati

Posts: 462 I get a PAR of (midrange numbers) 100 at the bottom and a PAR of 1500 at the top, PAR roughly drops about 30-75 PAR per inch of depth, so 5 inches down in the tank the PAR is around 1000, 10 inches down it's around 600, so at about 17 inches from the bottom of the tank i'm getting around 500-600 PAR 10 inches off the bottom the PAR is around 300-400, 5 inches off the bottom PAR is between 200-300, though you have to take into account the outer rim of the bulb gives you a PAR around 100-200 5-10 inches off the bottom

 

the red planet is around 13-15 inches off the bottom of the tank, it's getting 398 PAR off the the side, on the top of the red planet i was getting a PAR around 450

 

i had to hold the meter and take the pics myself so it wasn't easy, i wrote on tape all the numbers i was getting throughout the tank i'll work on getting that pic tonight

Here's the pic:

Edited April 20, 2010 by zygote2k

[ctenophore]

I'm assuming the 40 degree optics?

 

That is a nice aquascape.

[zygote2k]

those are 40 degree optics, 6" from the surface.

[zygote2k]

anyone considering an LED upgrade/replacement should look here.

[Coral Hind]

anyone considering an LED upgrade/replacement should look here.

 

Is there a link missing or are you talking about this post?

[Origami]

Beeker's 200-gallon PAR38 lit tank is here: http://www.reefcentral.com/forums/showthread.php?t=1805886

 

Here's the thread where PAR38's are being discussed.: http://www.reefcentral.com/forums/showthread.php?t=1746535

 

They use these PAR38 spots available at Nanotuners: http://www.nanotuners.com/product_info.php?cPath=74&products_id=623

 

(I had to look Beeker up on RC. Looking at nanotuner's best selling list, it seems that DIY LED builds are becoming more popular.)

[zygote2k]

I think after seeing the very impressive par values for these lights, people will be more willing to make the switch.

The pros far outweigh the cons- no heat, no spectral shift, no degradation of the fixtures and components due to heat, no bulb replacement for 5+ years, low power consumption, par values greater than a metal halide or vho.

If you price them, they are in the halide range or slightly lower.

[rocko918]

Rob I applaud your dedication to LEDs and these PAR38's. Just because they have great par does not mean everyone is going to like them. I for 1 think the spotlight looks weird and would not like that in my tank. I have looked at all these diy leds but don't see the advantages like you see. The long term effects have not been proven. Its the hot trend right now and when they come down in price and the technologies gets better, which it always does then maybe i will look at it. But when I have a lighting system that works and get the colors, growth i like, no need to change it.

 

I like the old saying. " If it ain't broken...." well you know the rest.

 

just my 2 cents.

[ctenophore]

Lumens per watt they are about the same as MH right now, maybe a little above. But they direct all their photons in one direction, which makes them better in that respect.

 

Lumens per dollar is a different story. MH & T5 still win hands down here. Maybe not in a few years though.

 

If I could justify the $$ to retrofit my display tank I would probably do it, especially with summer coming as 3x400w MH adds a lot of heat. But it would take 2 dozen PAR38 bulbs to deliver the same amount of light, that's a lot of upfront cash for a long term ROI. Kind of like solar panels. Maybe if the gov't would give us tax incentives for switching out our aquarium lighting

[zygote2k]

I don't know if they have enough power to reach the bottom of your tank. What are the current par values on the bottom under the halides?

I believe in some instances such as yours, that halides will be better overall due to the extreme depth of your tank. For tanks less than 36" deep, these lights are ideal.

Edited April 21, 2010 by zygote2k

[zygote2k]

Rob I applaud your dedication to LEDs and these PAR38's. Just because they have great par does not mean everyone is going to like them. I for 1 think the spotlight looks weird and would not like that in my tank. I have looked at all these diy leds but don't see the advantages like you see. The long term effects have not been proven. Its the hot trend right now and when they come down in price and the technologies gets better, which it always does then maybe i will look at it. But when I have a lighting system that works and get the colors, growth i like, no need to change it.

 

I like the old saying. " If it ain't broken...." well you know the rest.

 

just my 2 cents.

 

I agree that if you have an existing set up that works fine, it is kind of wasteful to change mid course, but if you are in it for the long run, it still might be cheaper. As far as the spotlighting effect goes, it's definitely not for everyone. That's why they have different optics available like 60 or 80 degrees- they'll spread the light much wider but at a decreased par value- how much remains to be seen. If you can get Troy to measure his 60 degree optics with a PAR meter, then we can have that info on hand.

[ctenophore]

I don't know if they have enough power to reach the bottom of your tank. What are the current par values on the bottom under the halides?

I believe in some instances such as yours, that halides will be better overall due to the extreme depth of your tank. For tanks less than 36" deep, these lights are ideal.

They have plenty of power to reach the bottom. Their intensity isn't being debated, rather the overall amount of light they put out. Think of a pressure washer nozzle vs. a fire hydrant. Both will take scum off a sidewalk, but the hydrant will spray a lot more water out over a greater area. The problem with the LEDs is that two PAR38 bulbs cost as much as a decent used 400w MH setup, but you need 8-10 bulbs to equal the spread intensity of the MH.

 

To answer your question, I have no idea what the PAR levels are on the bottom. I have had my PAR meter sitting next to the display tank for 2 years but have never measured it It is enough for clams and sps to sit on the sandbed though.

[Coral Hind]

You need to put on that weight belt and take some readings for us.