Downgrading aquarium need LED advice from rapidled kit.

[scoot15638]

So long story short, i am downgrading my old 45gallon bowfront to a 20 gallon IM Nuvo aquarium i snagged on black friday. Currently over my 45 i have the 24LED ultra premium kit from rapidled with 2 rapidled 4 diode UV led's in the mixture with it. They are some high powered led's, let me tell you. I keep the whole thing at less than 60% without optics. (about 2 or 3 inches from the water.

I would like to salvage my LED's that are currently on an 8x20 black aluminum heatsink, and buy a vesa mount/arm and put it over the tank as high or low as it needs to be. A nice clean look.

Now for the tricky part, should i leave the fixture alone? Add the 80 degree optics that came with the kit and put it wayyy above the tank? cut about 6-8 inches off the heatsink(which may not look as nice) and use 8 led's for each meanwell driver instead of the 12? Buy a completely different heatsink and use 8 led's?

I am leaning towards just keeping the fixture as is, and putting it high above my 20. Even though the heatsink is almost the entire length of the aquarium.

 

[sfsuphysics]

Just because your new tank is smaller doesn't mean the LEDs will be that much more powerful. How much taller is the 45g tank than the 20g tank?

I would just play around with what is most pleasing to your eye. My only concern without optics you're going to get a huge spread of light, out of the tank, against the glass, etc, which would have me leaning towards using optics. Even with 80° optics you're going to get a light spreading out about 1.7 times the height that you put it at, so 20 inches from the bottom of the tank is going make a light cone that 34 inches wide on the bottom (ignoring the refractive bit due to water). So I would still keep it close to the tank, just turn the power down if necessary.

 

[scoot15638]

Yea I may just do the least amount of work and keep a is. I have the LED's over my 45 turned down quite a bit. I can guarantee that they will cook that tank if turned up all the way. Only reason i'd put the 80 optics on it is because i already have them.

 

[scoot15638]

I found some cree xpg/xte 45 degree lenses on ebay for like 3 bucks. I may just order them and add them on to it, unless i decide that i need to get the 30 degree ones.