LED's

I'd rather replace the MH with LEDs

It can be done, but not cheaply unfortunately. To DIY it yourself properly, it's going to set you back about $250-$300. One thing to think about here is that you recoup your invenstment in about 3-4 years between not having bulb replacement costs, and reduced energy consumption.

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Originally Posted by evilc66

Heat, or lack thereof is one of the biggest boons to LEDs. Being able to dynamically adjust your color tamp and brightness on the fly is pretty cool too. Our understanding of LED technology is increasing. It's far better than what we knew 5 years ago when the first Solaris came out and everyone complained about them bleaching corals because the light was "not bright enough". Silly poeple.

Seeing as you are 20-30 minutes from me, you could always stop by some time and see what I have. Maybe a 40 Breeder lit by 60W of LEDs keeping sps would turn your head? ;)

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Sure would turn my head!!!

I just got back from a local reefers house (he is on RC) to measure his PAR from 18 Cree LEDS. He has 9 cool white and 9 royal blue on the array. I could not believe it when I saw what the measurements were.

The lights are 5 feet (yes 5 feet) from the bottom of the tank. There are shimmer lines just like the halides (optics turns the LED's in point source) and the par on the bottom of the tank is 180-200!!!! That is what I get from my 250's and they are 14 inches from the water not over 4 feet like this tank (4 feet to the top). I still cannot believe it!!!

There should be no doubt about the ability of LEDS to light up a tank. I installed 2 of the 70 watt AI units about a month ago on a 24X20X20 Cadlights Pro tank. I initially set the White output to 65%, believing that was about the same as the MHs I replaced (based on appearance only as I do not have a PAR meter.)

I proceeded to bleach everything in the top 1/3rd of the tank, including SPS. Even my RTBA went into hiding. I now have the power reduced to 35% and everything is "getting happy."

The PAR output of the 3 Watt Crees is very deceiving - It's a LOT more than similar "looking" MH. On RC, a user named Santoki had a DIY LED build using Crees that is very similar to the AI's in most every way - Including the 40 degree optics. He did a great job documenting the build, including PAR testing and demonstrating the results on his tank (SPS.) He has them mounted on his ceiling about 6' above his tank.

He measured PAR of 1028 in 12" of air and 984 at his substrate in 15" of water - No wonder I almost cooked everything. (In my defense, I didn't find the PAR values until after I had installed my lights.)

IMO, LEDS will completely replace MH as the cost of acquisition comes down - There's simply no reason not to.

• Better quality light - Almost all of it is in the spectrum used for photosynthesis (PAR.)

• Infinitely Variable color and intensity

• Low power use (PAR wise, 70 Watts of LED can equal about 250 watts of 20K MH)

• Almost no heat which allows for passive cooling or virtually silent fans.

• No bulbs to change or color shifts (Bulbs last 12+ years - and then output reduces by about 30%)

I'll never go back - Here's a FTS of my AI powered tank for reference. I do have a bit of spotlighting that will disappear as soon as my hanging kit arrives.

http://i786.photobucket.com/albums/y...l/DSC_0917.jpg

I will definately be using the dimming function of my profilux on the LED arrays I am going to buildto try out. I am still astonished at teh output for the amount of wattage. This is finally a light that gives more out than you put in in terms of energy.

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Originally Posted by Mike

I just got back from a local reefers house (he is on RC) to measure his PAR from 18 Cree LEDS. He has 9 cool white and 9 royal blue on the array. I could not believe it when I saw what the measurements were.

The lights are 5 feet (yes 5 feet) from the bottom of the tank. There are shimmer lines just like the halides (optics turns the LED's in point source) and the par on the bottom of the tank is 180-200!!!! That is what I get from my 250's and they are 14 inches from the water not over 4 feet like this tank (4 feet to the top). I still cannot believe it!!!

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Sounds like he is using some fairly tight optics. Good results though. My PAR38s are mounted 32" above the sand with 40 degree optics and I hit about 120-130 PAR on the sand.

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Originally Posted by CalmSeasQuest

There should be no doubt about the ability of LEDS to light up a tank. I installed 2 of the 70 watt AI units about a month ago on a 24X20X20 Cadlights Pro tank. I initially set the White output to 65%, believing that was about the same as the MHs I replaced (based on appearance only as I do not have a PAR meter.)

I proceeded to bleach everything in the top 1/3rd of the tank, including SPS. Even my RTBA went into hiding. I now have the power reduced to 35% and everything is "getting happy."

The PAR output of the 3 Watt Crees is very deceiving - It's a LOT more than similar "looking" MH. On RC, a user named Santoki had a DIY LED build using Crees that is very similar to the AI's in most every way - Including the 40 degree optics. He did a great job documenting the build, including PAR testing and demonstrating the results on his tank (SPS.) He has them mounted on his ceiling about 6' above his tank.

He measured PAR of 1028 in 12" of air and 984 at his substrate in 15" of water - No wonder I almost cooked everything. (In my defense, I didn't find the PAR values until after I had installed my lights.)

IMO, LEDS will completely replace MH as the cost of acquisition comes down - There's simply no reason not to.

• Better quality light - Almost all of it is in the spectrum used for photosynthesis (PAR.)

• Infinitely Variable color and intensity

• Low power use (PAR wise, 70 Watts of LED can equal about 250 watts of 20K MH)

• Almost no heat which allows for passive cooling or virtually silent fans.

• No bulbs to change or color shifts (Bulbs last 12+ years - and then output reduces by about 30%)

I'll never go back - Here's a FTS of my AI powered tank for reference. I do have a bit of spotlighting that will disappear as soon as my hanging kit arrives.

http://i786.photobucket.com/albums/y...l/DSC_0917.jpg

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This is what I have been trying to tell people for years. So many people initially made the mistake of trying to match LED setups lumen for lumen with MH with disasterous results. It's all down to the relatively selective spectral output of LEDs, and the crazy output of royal blue LEDs, which are the closest LEDs to the peak photosynthetic response of most corals. PAR is in no short supply with LEDs.

He is using 8 degree optics on his.

Hrm I'm thinking for the price I might go with the Maxspect setup (LED-G1-400-110W)

Evil,

How do you think corals would respond to UV LED's in the 350nm-400nm range?