sps under reefbreeders?

I'm starting to wonder why such high output LEDs are being used in these higher end fixtures if everyone ends up dialing them down halfway or more?

 

LOL Yeah I know it sounds stange but there are several very good reasons for this.I will let the led nerds fill you in.;D

 

Waiting for my tax returns then I'm getting a 24" reefbreeder programmable for my 29g. Maybe a vortec mp10 too. And a 20 g to build my DIY refugium. Getting lots of good advice on tuning the led power though. Good info!

 

Im no LED nerd, but I think it's so they can be usefull on so many different applications. You could throw one of theses or any LED fixture over a shallow tank and run 50% and then you could take that same fixture and put that over a tank thats +24 inches deep and still be okay(provided your optics fit the bill)

 

Why? Simply because LEDs are more efficient at lower intensities. At 350ma, you are getting about 140 lumens/watt with a 7500K Cool white XT-E. At 1500ma, you get about 428 lumens total, but only about 85 lumens per watt, as they are now 5 watt LEDs. So it is about 1.6 times (60% !) more efficient to have more LEDs at 350ma, than it is to have less LEDs at 1500ma. It may cost more up front, but you will
a) increase efficiency
b) reduce heat
c) increase the diodes lifespan
d) have the ability to spread the intensity over a larger area, ie. more LEDs on a larger fixture is more efficient than the same amount on a smaller fixture, as the intensity can be spread more effectively.

I hope that is a satisfactory answer to your question.

 

I second the Red Sea Pro

 

That is also part of it, if you manufacture a fixture, why make a wimpy version for shallow tanks, and a powerful version for deep tanks? The right optics will make a huge difference as well. The ability to dim also allows you to slowly dial up the power to provide more light when you first make the switch. Studies have shown that higher amounts of light cause an increase in coral fluorescence (the absorption of one color, and reflection of another, in corals this is caused by Chlorophyll a and c, and a variety of chromoproteins, which the coral uses to convert relatively useless light, like yellow, into red, for example, which not only looks nice to us, but also creates a spectrum useable by the coral for photosynthesis. Another use is as a natural sunscreen, some chromoproteins will adsorb harmful UV radiation, and reflect it as a harmless visible color, which may or may not help with photosynthesis, but can certainly look nice to us.) Higher light also increases the growth rate of corals, as I am sure many of you guys have experienced, under LEDs or not.