Corals losing color

[HWDylan]

I have a 75gal tank that has been running for about 8 months now. It is lightly stocked with fish and small coral frags (some LPS some SPS). What I have noticed is that when ever I buy a frag of coral from my LFS it is bright and colorful and then after about a week or two in my tank it just turns to a pale version of its original color. The LFS I purchase from runs everything under radions and I am using DIY LEDs on my tank. Are my lights too bright maybe? Some corals do great like my blue tort but other things like my meteorshower has lost most of its color.

I was wondering what could possibly be causing this loss of color. It isnt a browning out like you see with excess nutrients but rather a general loss of color.

Here is my tank info:
75 gallons - 55 gallon sump
NO3: 0ppm
Cal: 435-450
Alk: 9.8-10.0 dkh
Mag: 1500sih
PO4: 0.01
Salinity: 1.026

Lights are DIY 3w Cree LEDs:
2 greens, 2 reds, 4 blue, 8 UV, 28 Royal blues, 18 cool whites.

Lights are 8.5" off of the water surface.

[Kyle918]

I bet your LEDs are your problem. That comes out to 186 watts total. The radions you mentioned have around 136 or something a channel... One radion has more wattage than your entire LED setup and one radion I don't think is enough for a 75 gallon, so you at 186 watts I believe may be under powered and can be what is causing your bleaching.

[tylersarah]

Yep, I too believe you need more light.

[HWDylan]

Interesting.

I originally bought the Rapid LED 75gallon retro fit kit that came with 48 LEDs and I actually added to it. So I guess Rapid is selling a vastly under powered product?

The LEDs have 80 degree lenses on them if that makes a difference.

[thegrun]

You really need to take PSAR readings of your tank, otherwise all is pure speculation. You could just as easily need mineral supplementation. I recently tried the Red Sea color program and the color in my corals improved significantly.

[figuerres]

Originally Posted by Kyle918

I bet your LEDs are your problem. That comes out to 186 watts total. The radions you mentioned have around 136 or something a channel... One radion has more wattage than your entire LED setup and one radion I don't think is enough for a 75 gallon, so you at 186 watts I believe may be under powered and can be what is causing your bleaching.

I do not know if the tank needs more light but please lets check this one thing:
a "Watt" is a unit of ENERGY not of light.

an old fashioned light bulb puts out a lot of "Watts" in the form of HEAT.

measure light , not heat. switching from say metal halide to led and counting watts of heat is really wrong.

[HWDylan]

Originally Posted by figuerres

I do not know if the tank needs more light but please lets check this one thing:
a "Watt" is a unit of ENERGY not of light.

an old fashioned light bulb puts out a lot of "Watts" in the form of HEAT.

measure light , not heat. switching from say metal halide to led and counting watts of heat is really wrong.

That is what I thought. The comment about watts confused me. I was under the impression that the amount of light I was putting on the tank could potentially be too much and be burning the corals up.

That is why I came here to get a second opinion. I really need to get a hold of a PAR meter and really see. Those things cost a small fortune though...

[figuerres]

Originally Posted by HWDylan

That is what I thought. The comment about watts confused me. I was under the impression that the amount of light I was putting on the tank could potentially be too much and be burning the corals up.

That is why I came here to get a second opinion. I really need to get a hold of a PAR meter and really see. Those things cost a small fortune though...

Light is a kind of tricky subject with so many folks used to thinking of watts and not of real light.
also be aware of the "inverse square law of light" that moving a light one foot farther back divides the light strength in "foot candles" by 4

http://en.wikipedia.org/wiki/Inverse-square_law
https://en.wikipedia.org/wiki/Watt

LED wastes less energy and can put out a *LOT* more light per watt than other kinds of lights.

[Fizz71]

Watts are easier to measure. We use watts because that's what can be measured by the MFG without taking any other factors under consideration (distance to water, distance under water, etc.) then we use watts of one unit to compare it to another unit of similar style to get a general sense of output. But you have to compare apples to apples.

Anyway...you're right...the only way to really know is to get one of these bad boys.

Also know that overall color temperature of the light also affects the color of the coral. I have 250W 20K Radiums MH bulbs over a "blue polyp cap" that most people don't like because the polyps are the only colorful part of the coral. The cap is usually brown...under 20Ks the cap is a beautiful green. It was brown when I bought it.

[krzyphsygy]

Here's a different approach. How many fish do you have in the tank? What type of rock did you start with?
I had a very similar problem that I was able to fix. All my corals got really pale, and I had a light fish load. Zero N03. ect ect.

So I increased the fish load in the tank from 4 fish to 10 and feed 2x a day, I have a good skimmer so that kept nutrients under control. Slowly my corals became much more colorful and better polyp extension.
My corals were starving for fish poop. Broadcast feeding the corals did not help, I needed fish and thats what fixed it.

[danil]

Originally Posted by HWDylan

That is what I thought. The comment about watts confused me. I was under the impression that the amount of light I was putting on the tank could potentially be too much and be burning the corals up.

That is why I came here to get a second opinion. I really need to get a hold of a PAR meter and really see. Those things cost a small fortune though...

With LED I would strongly recommend to get PAR meter. You don't need a "full" meter you can just get a sensor for $139 and use it with any common voltmeter. Apogee sensor is good enough for us.