Originally Posted by burrows14 (Post 544485)

Any updates??? Im starting to lean towards led's these days. I keep mainly SPS in a 24"deep tank. Thanks in advance:smile:

Originally Posted by TheDogFather (Post 533734)

Below is the non scientific Vertex Illumina SR 1200-200 PAR measurement taken with a Apogee Quantum Meter. My tank is 18" tall and the fixture is 6" above the surface.


White 100% - Blue 100% - Royal Blue 100%

759 about 5mm below the surface

484 On left frag rack

392 At top right coral colony

242 Center of Red Monti

227 Center of Clam

185 Front Elegance Coral

214 Bottom right middel of tank

148 Bottom rear of tank


http://i390.photobucket.com/albums/o...00-200_PAR.jpg

Originally Posted by Ron99 (Post 545041)

Any updates or more then and now photos? Personally, I'm not super impressed with the PAR readings you showed so far. For optimal growth of SPS you want between 400 and 500 PAR. My DIY LED array achieves that in the middle level of the tank (10 inches down my 20 inch deep 75 gallon) at less then full power with the array 6 inches above the water. If I turn it all the way up and lower to 3 to 4 inches above the water I get way more. I get well over 250 PAr at the sand bed 18 or 19 inches below the water surface.

Your clam may do alright but as I understand it clams need 250 to 300 PAR (I may be wrong on that but it's the number I recall).

Originally Posted by TheDogFather (Post 545405)

That's nice Ron99 but this is not a contest and what makes you think you need between 400-500 PAR to grow stony corals well? My SPS and clams say otherwise.

I'm not going to get into a PAR contest with your DIY fixture, I get excellent growth (at 50% power I might add) and my clams are growing very well. The 48" Vertex Illumina LED comes very close in PAR output to my previous fixture, ATI PowerModule with 8x54W T5's and that fixture is no slouch.

I'm guessing your DIY uses optics to achieve higher PAR values but at the cost of spread so you'll have to hang it high to get decent coverage thereby negating all that extra PAR...

-TDF

"Stoney corals appear to photosaturate between 400 and 500 PAR so having 700 or 1000 PAR is probably pointless other than for bragging rights. I doubt it will do the corals much good." -Ron99

Originally Posted by ReefOcean (Post 545444)

Well this is a review and discussion forum, LED comparisons are relevant.

I have to agree with Ron. For that much money, I would expect outrageous par.

Judging by those readings, it is only about 20-25 percent better than my light which is a tenth the cost, a fifth the size and made by communists.

The readings are probably not accurate though. I wager that the vertex must have better output than that.

Originally Posted by Ron99 (Post 545563)

Not trying to make a competition out of it, just trying to give some perspective on relative performance of different configurations. As for light requirements for stony corals, that varies widely. LPS generally are lower light, montis would probably be described as moderate to high light and most acros would need high light for best growth and colour. I didn't say you had to have 400 to 500 PAR to grow them but for "optimal" growth and colour my reading has indicated that 400+ PAR is best and as you noted by quoting me from my build thread there is evidence that they photosaturate by 500 PAR so more than that is not really needed. Hence my conclusion that 400 to 500 PAR is optimal. I have a great example in my own tank with a superman monti. My own colony is in the top third of the tank and the base is a nice deep blue colour. I have some frags down on my sand bed and they are growing just fine but the base is a much more pale blue colour. You have only been running this fixture for a month or so. I will be curious to see how everything is doing in 6 to 12 months.

As for my fixture, yes I used 60 degree optics but spaced my LEDs out evenly over the tank so I do not sacrifice spread. I have 4 rows of LEDs, with 3 inches between the rows and the LEDs in the individual rows are 2.25 inches apart. I actually use fewer emitters then the Vertex unit does. I have 80 Cree XR-Es. Vertex uses 128 Luxeon Rebel emitters (pretty good LEDs for the record, equal to or maybe even very slightly better then the XR-Es I used) for their 4 foot fixture. That is 60% more LED emitters but yet it apparently produces less PAR in the tank. I also do not have to hang my fixture higher because of the overlap in the emitters. I can lower it to about 3.5 inches above my water without any major spotlighting or loss of overlap. I currently have it about 5.5 to 6 inches above the water and it is producing the PAR numbers I mentioned at that height.

Basically it is all down to how you configure the LEDs and optics and I guess I do not really understand Vertex's design choice as they could have achieved higher effective output with fewer emitters. Space them out evenly over the tank to get coverage and then choose the number of emitters and spacing between them appropriate for the optics you want to use to produce X PAR at Y depth. Want more PAR for a deeper tank then use more emitters spaced more closely together with tighter optics. Have a shallower tank or don't need really intense light and you can space the LEDs farther apart and use wider optics or even no optics at all for only low light corals or a fairly shallow tank.




I guess that is my point of contention. I question whether the performance justifies the price. Out here in BC that fixture will be $3248 after tax. That's a good chunk of change and 2.5 times what I spent on my DIY fixture.

As for output, his PAR numbers look to be about what I might expect having all the emitters clustered down the center with no optics. High PAR up top and down the center of the tank with a rapid drop off as you go deeper into the water and also as you move to the front or the back of the tank.

As I mentioned before in other threads, I think LEDs are the future of reef lighting but what I see happening is that people will $h1t on LEDs because they spend huge amounts of money on a fixture then eventually complain that the performance relative to their 250W or 400W MH is poor and that LEDs are no good for reef lighting. It taints LEDs in general when it was really down to the design of the particular fixture.

Originally Posted by gucci17 (Post 553522)

Any updates?