View Full Version : LED optics needed for 45g cube?

07/21/2015, 06:51 PM
I have recently bought a marineland 45g cube dimensions are 24x24x19.

I am planning on building a DIY fixture using one of rapidled's 12''x6'' heatsink with 30-40 leds, with it hung about 12'' over the tank. I'm not too concerned with coverage over the width of the tank with the heatsink being 12'' long, but I am a little concerned with coverage over the depth. I have read the article led group buy about optics, and I am leaning towards 60 degree optics, or no optics at all. If at all possible, I would like to reduce light spillage due to the tank being in the living room of my house.

This will be an sps dominate tank BTW.

07/22/2015, 05:38 AM
Run optics for no other reason than to avoid the spillage.. and with 19" depth and 12" over the tank they will help get the light down low..

07/22/2015, 06:28 AM
Thanks for the input. Any suggestion on which optics to use? Do you think 60 degree would be ok?

07/22/2015, 06:51 AM
Just from my own setup i have 90 degree optics and the tank is about 24-27 inches deep, fixture is 2 feet above the tank and blues are at 75%, whites at 35%, and it reaches the bottom just fine, i have a maxima and dersa at the bottom along with some sps frags all doing good and growing. If i turned them up anymore i would bleach the coral that is about 12 inches from the top (I turned it up 3% and saw the color getting washed out). I would go no more than 90 degrees personally to keep a decent spread.

07/22/2015, 08:59 AM
90 degree optics it is. Thanks for the help.

07/22/2015, 09:19 AM
Make sure to come back and show us your complete project :)

07/22/2015, 10:15 AM
Will do. I'm still in the planning stages. It'll probably be a little while before it's done.