I was asking a LFS guy about running different T-5’s over coral. He suggested I take my current bulb combo (2 420nm actinic, 1 ATI purple plus, 1 10k daylight) and instead replace the 10,000k with an ATI blue plus.
The question here is, do you NEED a 10k bulb?
Stupid question, I know. Their tanks just look so good under those lights!
Thanks
-Josh
IME no, you really need to look past the kelvin rating and look at the wavelength peaks
if you look back through the forum you should find a presentation from Captain Ken about the wavelengths used by most zooxanthellae found in our corals which for the most part rely on 420nm, 445nm and some in the red zone of 630nm, so beyond providing the needed wavelengths for optimal photosynthesis, everything else is for our visual pleasure, IMO…
If going with ATI bulbs I would go with 1 true actinic( weak colored bulb but peaks at 420nm) 2 blue plus nice blend from 420-453nm(much better then the purple bulb), 1 10k to help with actual daylight and not just pure blue look in the tank. 10k to me helps dim the blue bulbs a little and shows nice coloration when combined.
yeah, the “peaks” are important… from there its just preference on how blue you want your tank to look.
I love the blue plus bulbs… good par and color.
i have 4 rows blue plus, 1 aquablue special, and 1 actinic…
i do think my tank would benefit from more 420 actinic though…
I had the “stock” bulbs that came with my fixture . . . can’t remember the name. But when I added the Aquablue Special, 2 Blue +, and an Actinic from ATI i noticed a SIGNIFICANT change in growth and tank health. The color is very nice as well.
I had a 10K bulb, and have seen better results by using the bulbs above. The Actinic will help you out with hitting that 420nm peak, it would be a good buy.
IMO, the Purple Plus looks too red/purple, and messes with the way the colors of the corals look . . . everything looks purple, even green. lol BUT, that’s just my opinion
Here are the coral chlorophyl utilization curves you mentioned, Dave. the two types grow best at 430nm and 453 nm. most of our bulbs have very little in the second peaks beyond 500 nm. and sea water absorbs that part of the spectrum with increasing depth. leaving mostly blue for the corals.
10K T5s do have a good amount of blue in th 420 range, its just whited out bythe extra green, yellow, orange and red.
when you overlap a couple shades of blue you get a combined wider and flatter blue curve coverage. which is good.
Ken…
what would be your ideal T5 combo of ATI bulbs?
for a 6 row, and a 4 row fixture?
and how do t5 actinics stack up to vho’s in your opinion?
Put me on the spot, Eh? well, for a 6 bar, I might try 3 blue plus , 2 actinic and 1 50/50. the 50/50 would have a good dose of actinic in it and a little white to brighten the tank a bit. same idea for the 4 bar. one 50/50 , 1 actinic and 2 blue plus. that should fairly evenly cover both blue peaks and a little brightness.
the aquablue special has a lower blue peak, and the 600 range peaks are off the usable mark. so why bother.
T5 are HO and VHO are , well Very HO. more watts and higher amperage. so VHO seem to work better. but T5 focus better with reflectors. so who knows. but now Sunlight Supply has come out with the first true VHO T5 light strip and lamps. Id like to see one of thos in action.
http://reefbuilders.com/2011/07/21/tek-wave-vho-t5-fixture-sunlight-supply-finally/
or their newest combo to come out soon, with LEDs and T5s. They dont say if the T5s are VHO or HO?
http://reefbuilders.com/2011/11/22/sunlight-supply-ss-led/