a complex question to answere, but here goes (you'll notice I've spent considerable time and money testing these critter) I have several fixtures in opperation, and have constantly been tweaking them in the search for a near exact replacment for my display tank lighting spectrum. as well as evaluating different violets to find the best ones for me. (I like lots of violet, which is contrary to what most like so I need to run them very high and have lots of them to get enough for my taste)
originally, about this time last year when I first added violet to my lights the max recommended rating was 700mA just like all the other LEDs I had. since my goal then was to find just the right mix of leds to get a color I liked I went with simple one string one driver approach to my builds and just swaped LEDs until I got where I wanted in terms of color. (basically many prototypes and revisions leading two what I'm about to start building this spring for my dispaly).
the first Light was from Aquastyle Online, and those never were turned up past 400mA as with the optics there was no need over my frag tank, but the vilolets burned up anyway. still working by the way, just slightly dimmer as I didn't get the burnt plastic dome poped off fast enough and some of it stuck onto the secondary optic, I never messed with replacing them just left them in place.
second light a 12 led setup using three violets ran at 580mA on a cheapo driver over a ten gallon. masive heatsing and fan cooled, stayed pretty cool with out the fan but overkill was the way to go at the time. Violets lasted just under 3 months before burning, also still work but badly damaged as the secondary lense melted into them (vendor was nice enough to send replacements with the advise to run them below 500mA, they then posted the 500mA recomendation on their site) So I put the replacemnts on a new fixture and set it to 500mA per thier request. also ordered up new ones from two other sources, Steve's LED and Rapid for the first fixture as a test, along with one of the replacemnts. I modded the fixture to give strong airflow across the lenses as well as heatsink to test a theory about heat on the lens. the replacment burned up anyway so it's not a heat related issue.
first ones from Steve's burned (they sent replacements that are a newer version which I have not installed yet and am hopeful they will not have the same issue) Rapids have had no issue on any of my fixtures to date and have outlived all the rest I have tried to date. (i've had some running at 680mA since last March)
So, based on all of that I presently run them all at 680mA max as everyone claims 700mA can be done without any problems. (a true statement hands down for what I've gotten from Rapid) Steve's LED assurse me thiers will too and the bad ones were a fluke or manufacuturer defect of some form.
long winded way to say that the spec sheet dosn't mean squat, the spec sheet is only for the LED die inside the packaging (the tiny little metalic square piece at the center that lights up) No one, I mean no one publishes spec sheets for the packaging the die goes into, or how they are then mounted to the star chip, so their are an auful lot of vareables out there that can affect performance. the die can run at 700mA al day long with a good heatsink but the plastic may or may not be able to tolerate UV light.
SemiLED (makes most of the UV LED dies used by everyone) now cautions about that on thier data sheets.
sorry I think I over answered your question
