Light requirements for a reef tank

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Aquarium Advice Freak
Jul 22, 2012
currently i have a fluval aquasky 2.0 set up on my 40gal breeder tank. which was fine when i just had fish and some hitch hiker xina. but i am looking to expand now into the coral realm. and think ill be picking up a new light for that.
my question is what light spectrium/intensity should i be looking for. its been a while and i dont remember what light i had on my old tank. or id just buy it again. thanks for your time.

current lighting


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Spectrum and linens aren’t really what your looking for, spectrum is the color of the light, 20,000k is more blue than white while 6500k is almost all white (fw planted look) and lumens is basically brightness. If your looking at getting into coral I’d recommend a quality lighting system, as you’ll almost always spend more on multiple cheap units before upgrading to a good light anyway. What’s your budget?
200ish give or take. i seem to recall 14000k being a good range wasn't it?
nice and blue
Again temperature or kelvin doesn’t make it a good light for coral, as to wether 14k is a good look for the tank, that’s a personal opinion, to me it’s whiter than I typically run my lights if I have a choice. $200 is going to be hard to light a 40b for reef quality lighting, back when I was last in the hobby there were black box lights on Amazon that were in the 100-130 per light range it not sure if they’re still available. 2 ai prime 16hd would work well for you but that’s double your budget roughly
Not good. 27 watts and 64 leds= less than a watt an led which won’t really support much. Par is probably pretty bad. If you want any lps or higher light softies I’d upgrade for sure
Thanks for the info guys! And I looked up the par and it’s like 60 something so pretty weak for sure. XD I’ll check out that light thank you for the suggestion.
FWIW in regards to spectrum, my light is fairly blue/teal and these are my settings and what temp they are


Decided to go with a fluval marine 3.0 paired with the aquasky I had. Will upgrade to a second 3.0 eventually.


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That’s still going to leave you on the very low end of light for photosynthetic corals. Could probably get away with some mushrooms and other softies but that’s about it
Yes I’m going to focus on low to medium light corals. The way the aquascape is almost all of the coral space will be at the 6inch or less distance from the light. The lower half I want to keep open to max out sand surface space for sand sifters/burrowers
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