uvc... the bringer of death and/or blindness to all who face it prevails once again!
i'm right with you on this one tech... been there, done that myself... 50 gallons, 15 watts... slow the flow and good to go! it's exposure time and distance from the bulb that counts.
EDIT: i guess i should add to the original question since i have one too. they can get pretty hot. check your tank temps after adding one for a couple days. if your temp goes up you're sure to evaporate more.
Thanks for the thumbs up dude! I encourage input on this, from those who have actually ran/run UV--even if your results have-been/are negative. The more the merrier! Let's put the disinformation straight, once and for all!
15 watts on a 50 is a bit low. However, I'd still say the flow rate can be 50gph or even a bit higher though that UV unit.
I have found this, the Tomite stage lasts long enough, and most Tomites need long enough to "find" a host, that if the UV does not get 'em the first time, it will the second, or third.
This is only a bit less than 1/3w per gallon, this is lower wattage than I run on any of my tanks. It might take a few days longer than the higher wattage to be as "ICK effective", but ran 24/7 for long enough, I believe it good at being effective against ICK. Certainly, in a warm tanks, within days, you should notice a DRAMATIC decline on attached ICK, a couple of days longer, perhaps no ICK, etc.
I am super glad you documented that the lower wattage is effective. At the time I was running 1/3w and lower, I was not using the UV to fight ICK, only algae. Back then, I didn't even notice if was being effective or not on any of my tanks for ICK--just didn't expect that bonus! And, it was too long ago.
Glad you like/love UV as much as myself! BIG, OORAH!
Regards,
TA