led optics

kratos1028

kratos1028

Active member
Not sure which one to get since I have a 24" deep tank. Would the 60 optics be fine or the 90? I don't want the light to be too spread like the 120.
 
this is from steve's site. What size tank are they for? are you using dimmable ballasts?


-For tanks up to 30 inches deep, no optics required

-For tanks deeper than 31 inches, 90° will be ideal

-For tanks deeper than 41 inches, 60° will be ideal

-For tanks deeper than 51 inches, 30° will be ideal
 
im sure you would, when you got the optics on its all about how high you have your lights for spread. Which optics?
 
They would be sitting about 5-6" from the surface of the water. The stand will be made for it sometime next week. My t5s are 1-2" from the water surface right now.
 
i think 90 is the best option, i never used just bare leds. i dont want the leds burning my eyes when look at them. 60 degree might be too narrow and cause color separation. optics are cheap anyway, you can always change them later if you dont like it.
 
Optics are also a magnifier of the light and make leds a lot more effective. IMO you will be fine with any of them with the exception of the 30's, however I would not buy or build a fixture without them no matter how shallow the tank unless I was growing low light corals or FOWLR.
 
spotlighting seems to be a DIY error caused by spacing the LEDS to far apart. Get a little protractor you can measure the light and see the visual. Standard protractor is 30 60 90.
 
I was under the impression that spotlighting is when you use to high of optics on every led causing it to shine straight down instead of spreading the light. For instance, i thought you use 90 degree optics on the outside to minimize light spillage but wider optics inside to cover the area
 
zoomcorvette said:
I would not buy or build a fixture without them no matter how shallow the tank unless I was growing low light corals or FOWLR.
Click to expand...

That's pretty mis-leading info. Optics are not really required unless high PAR penetration is required. I have burned and bleached many SPS corals,i was advised by my led vendor to remove the optics and problem solved,all my corals are much better,have regained their color and are happily growing. My units are 7'' above water line and i do not use optics.
 
optics focus the beam. Have you ever played with a magnifying glass and paper or taken the reflector out of a flashlight. Density of lights, height above water, coral species, are all required to properly size LEDs and optic choices. A 36" deep SPS tank will require tight optics but a 12" tank could use them if enough are used and the fixture is hung high enough. I built a bunch of DIY fixtures before I realized how much research is involved to do it right and get good coral growth. Again I would not even waste the money or time without optics. There is simply no good fixture without them.
 
Or you could have left the optics on and reduced the wattage {dimmed them} and saved money on energy. What wattage LED's are you using and do you still need a chiller with your setup?
 
I don't use a chiller and they are dimmed to 60% whites and 80% blues. I have 3 Neptune units over my 180g. We read PAR on sandbed and get 115 and 330 4'' from surface. With optics we were getting 13814'' from surface and 504 on the sandbed at 100%
 
Those are almost the same numbers I am getting with 3 watt cree LED's 60deg optics and run at 2 watts for long LED life on my 150 AGA which is a little deeper than a standard 180. Before today I had never heard of anyone with these par values without OPTICS. I cannot wait to see what the future brings.
 
You must log in or register to reply here.
Back
Top