Led vs PAR for coral

[dawguy]

Hi all, I've been running the 16 inch evergrow led units from reef breeders since Nov. Had some really go growth for a few months, but recently I started noticing some lost of color on the tips/surface facing parts of the corals.

If there is anyone else running the evergrows, what power levels do you have set for your blues and whites in your custom daily cycle?

Mine ramps up to a high of 100% blue and 70% white for a 4 hour block. I've dialed that down to 65% blue and 45% white yesterday to see if things get better.

Also, does anyone have a par meter that I could borrow to measure the readings by chance?

 

[Terrance]

How tall is your tank and are you using optics?

I have been running my value fixture at 100% both channels since my tank is 24" tall, at 8hrs long daily.

 

[1guydude]

I'm no expert and no scientist most of u know! However wat I know is that vhos and mhs and such put out a wider color of light on the color spectrum. Yellows and reds and such r common with white light. Purples and greens can be in the blues like 16k.
Soooo leds just spike in their color spectrums. Whites r whites and blues r blues. Not bad imo but ur light is stronger. Giving more of the light the coral.needs. ur.doing.well imo by turning the light down a bit and watching.
Sry no charts or In depth stuff but hths.
-d

 

[dawguy]

It is 24" tall and 90 deg optics.

 

[Terrance]

Depending on the depth of your sand bed, here is an approximate PAR value with fixture same as your Reefbreeders/(Evergrow OEM) Fixtures D120/IT20** series - Page 6 - Reef Central Online Community

I'm trying to borrow the club's PAR meter, but I can never remember to ask for it.

 

[iroll253]

I peak at 40/40% for a two hour block and have still melted certain colonies . however my sps have all grown substantially. Thus the reason for selling my unit and getting back on t5's

 

[dawguy]

Depending on the depth of your sand bed, here is an approximate PAR value with fixture same as your Reefbreeders/(Evergrow OEM) Fixtures D120/IT20** series - Page 6 - Reef Central Online Community

I'm trying to borrow the club's PAR meter, but I can never remember to ask for it.

thanks for the link. Looks like according to the charts, at 60/40 and approx 12 inch below (where I have most of the sps) I would get 400 par. I've read that sps likes to have 250 - 300, so perhaps I should drop down the power even further.

 

[tat2z_21]

I'm no expert and no scientist most of u know! However wat I know is that vhos and mhs and such put out a wider color of light on the color spectrum. Yellows and reds and such r common with white light. Purples and greens can be in the blues like 16k.
Soooo leds just spike in their color spectrums. Whites r whites and blues r blues. Not bad imo but ur light is stronger. Giving more of the light the coral.needs. ur.doing.well imo by turning the light down a bit and watching.
Sry no charts or In depth stuff but hths.
-d

This is a common misunderstanding, blue LED's are 460nm specific, while the white LEDs peak at the same 460nm, being that this is the exact range photosynthesis likes, this is why we can not judge strength of the lights by our eyes.

 

[Terrance]

There are many variations of white LEDs, such as warm white, cool white, and neutral whites, that peak at different nm.

Cool white is commonly used in the hobby that peaks at 460nm

The older model of reefbreeder consist mostly of warm white (not sure where that peaks at).
The newer model of reefbreeder has neutral whtie.

 

[tat2z_21]

There are many variations of white LEDs, such as warm white, cool white, and neutral whites, that peak at different nm.

Cool white is commonly used in the hobby that peaks at 460nm

The older model of reefbreeder consist mostly of warm white (not sure where that peaks at).
The newer model of reefbreeder has neutral whtie.

From what I understand all white LEDs have a huge spike in the 460nm wavelength, because they are blue LEDs with a phosphorus coating that allows a short spike of 460nm and allows a longer wavelength of yellow to make light appear to be white. What I am trying to get at is that having that much light in the specific range for chlorophyll a creates a scenario that the algae grow at a rapid rate, creating a spike in oxygenation, and the corals expell the algae. I could be wrong though

 

[dawguy]

FYI for anyone using reef breeders or evergrow alike. I asked Logan from reef breeders regarding my situation and he indicated that he runs his lights at 60% on his own tank.

 

[kpiotrowski]

FYI for anyone using reef breeders or evergrow alike. I asked Logan from reef breeders regarding my situation and he indicated that he runs his lights at 60% on his own tank.

too many variables. depth of tank, height of fixture above water, optics and spread you are trying to cover. led's have some crazy par high up but do drop of quickly the deeper and especially wider you go. 60% would be perfect for sps 8 inches below the water directly under fixture, but move that colony just a few inches over and few inches down with 90dg optics and it may not even thrive.

this is a huge dilema for me right now as I am setting up a 74x36x26 and for me at least, I would want 8 of those evergrows with 120 optics on the outsides and a few with 90's in the middle and then yes run them in the 50-70% range.

 

[Terrance]

8 is a lot. I think you would need 4-5 at most. I got 1 covering 24"x24", 2 of them would easily cover 48"x24" footprint even for SPS.

 

[kpiotrowski]

8 is a lot. I think you would need 4-5 at most. I got 1 covering 24"x24", 2 of them would easily cover 48"x24" footprint even for SPS.

I know, I know....just my OP having seen a par meter on an evergrow with 120dg optics. "All I need is 3" i have been told...on a 6 foot by 3 foot tank???? There is a reason I say I would "want" 8

on a 24x24? I would also do 1, however I can not buy into the claims that one units is good for 24x24 when the par drops off so much to the outsides and consider the fixture is rectangular...all things being equal the unit should be square with such a claim, or the claim should be it does a 24x30 or 24x34 or something. so if this is true, then does it really do a 24x24 well? or does it do a 24x18 well....when is it "well', "good enough" or just getting buy, compared to very well or optimal or overkill?

 

[glweek]

Kpiotrowski: EXACTLY. its always been so confusing when company's say they can get a 24x24 when the darn thing is twice as long as it is wide!

 

[TJL]

Been following this thread to see how it would go fact/myth wise. So now I'll throw my $0.06 in. The whole LED -vs- MH/T5 is a very complicated comparison in that we are trying to compare Watermellons to Grapes... both fruits and both similar shapes... but.... The facts are that photosynthesis requires a nominal range of light spectrum (400-700nm / violet to far red) to function well. The primary symbiotic algaes (zooxanthellae) that give corals their base colors are chlorophyll a ; absorbing light in 400-550nm 'Blue' and 650-700nm 'Red' spectrum, Carotenoids absorb light in 450-500nm Blue/Green spectrum and Phycobillines in 550-650nm Green/Orange spectrum. So in providing certain wavelengths in our lighting we can excite or encourage specific zooxanthellae to thrive or not. LED's are quite specific while T5 and MH are generally a little more wide ranged in their outputs. The downside with MH or T5 is that their spectral output degrades with time to the green-yellow end thus starving out some and encouraging other zooxanthellae to grow. With LED's we can build/create a very narrow range but usable light source that stays quite true for their duration with a fraction of the energy of other two sources and without the so-called 'garbage light'. Because of this it is easy to over-light our systems to match our visually perceived notion of how much light there should be. LED's are very difficult to accurately rate with our current 'Light Quantifying' instruments as they typically read/measure for all visible light spectrum. I spent a few years researching and educating myself on LED's before starting to purchase then assemble my own DIY lighting. My inspiration was to create a LED version of the Phoenix 14K lamp so using its spectral chart I aquired different colored emitters in what I believed to be the right ratios to re-create one, but without any garbage light or spectral degradation. I am extremely pleased with the outcome and most all corals have done exceptionally well. The exceptions have been some LPS that were over lit, even though I run my 96 3w LED's without optics at approximately 50% (emitters rated from 750-1050ma ran on drivers tuned to 700ma then controlled by Apex to 70%.
Bottom line is... that photo-active Corals/Plants don't care what the light source is... as long as they receive it at the needed spectrum and output.... 1000's of candles with tinfoil reflectors, incandescence, fluorescent, plasma, LED will all work... I choose LED's

Cheers, Todd

 

[burning2nd]

My evergrows are about 8" over my tank... blue running at 100% and white running at 75%
8 hr a day

acclamation took a week and a half.. from Mh
16 hrs of 100%
then 10% on both sides
ever other day about .5% increase. took me about 10-12 days to get to 100% on the blue side

I just replaced a LEd driver on one of my units though... Not ever a month old.. So i plan on stocking a extra one on hand.


I also agree with Todd... Just remove the science from it... we dont need to hear about all that... lol