Any Truth to the "old LED" Statement?

ReefMadScientist · Aug 31, 2015

So I have heard this statement MANY time in the community and not sure if its taboo or something to explore as a possibility. So as some of you may know, I have a never ending battle with cyano/weird bacteria on my sand and some rocks. After trying many different techniques, I am still cursed.

I was told it may be my lights. I was asked "how old" were they were as I was told that may be the source to my issue.

So my question to you, can OLD LED's - create bacteria blooms? lol.

And since we are at that, does the RED color create bacteria bloom growth?

eyesinthedrk · Sep 1, 2015

How do you define old?

ssdawood · Sep 1, 2015

Not an expert by any means but by old it might mean.

The intensity of leds has reduced by more than 50 percent since when they were new.

The spectral output of leds have shifted since they were new.

eyesinthedrk · Sep 1, 2015

I meant how old are the LEDs when this is supposed to happen?

I'm at 3 years on some black box LEDs with no evidence of this.

jt17 · Sep 1, 2015

Could also mean old LED technology, ie pre Cree.

Shep · Sep 1, 2015

I highly doubt it could be causing bacterial blooms, most bacteria are not photosynthetic and if they were they would probably be green because just like plants it would allow them to adsorb the most light. I could be wrong and you could have a photosynthetic type but even if you did I doubt old LEDs would make a difference. There is likely a different cause such as low flow or high in nutrients and there could be the unlucky possibility that the bacteria that are causing the bloom might not need any extra/special condition to grow. They are masters of evolution and can thrive off very little, so the strain you have could just grow despite your efforts.

TheEngineer · Sep 1, 2015

LEDs do age, but I agree with @Shep that it seems unlikely to be causing a bacterial problem.

LEDs "aging" depends on how close to their maximum output they are run, how many hours they are run and how well they are cooled. As they age they will produce less lumens of light per watt of power. The generally accepted lifetime is reached when the LED outputs 70% or less of the specified luminous flux output. For a CREE LED that is properly driven and cooled, that's going to be upwards of 60,000 hours or just shy of 7 years running non-stop. Now as they age you can expect to need to adjust the color mix, different colors are likely to age differently. That said, it is going to take quite a while to get to the point where you need to worry about that.

D maul · Sep 1, 2015

I think Shep makes a good point here. It may not be your lights, my dads eco rays have been running 4 years without a issue like your having.

Jimbo662 · Sep 1, 2015

I'm having the same issue and haven't figured out the root cause. Tank is a 50g cube with two MP10s. I've gone lights out for 3 days and reduced feedings. I only have two clowns and a shrimp. I can stir the sand around to bury it and the next day it's already starting to cover the sand. This past weekend I got a dragon goby and more snails to see if that will help.