I had one that worked for 3 months then died.
Tried another a few months later and it did not last long.
Best results of late have been this method as it worked quite fast in my frag system and is now destroying the hair algae in my 120 with no effect on corals, fish, or inverts.
API Algaefix every 3 days.
6 doses and 18 days later algae is easy to pick off rocks.
1/2 dose of fluconazole on day 18.
Within 3 days algae is 50% gone or whitish now.
Dosed the other half of fluconazole a week later with algaefix dose.
Algae is hard to find now and will do a algaefix dose once a week for a couple of weeks before adding back carbon.
Ran skimmer the whole time.
Will wait a couple of weeks before doing a small water change of 10 gal.