http://www.reefsanctuary.com/forums/...ing-dinos.html
http://www.canreef.com/vbulletin/showthread.php?t=21964
http://www.canreef.com/vbulletin/sho...inoflagellates
Things I did that were partially successful:
increased alkalinity
added refugium
increased water change frequency
increased water change volume
increased skimming (bought new one, actually now that I think of it 2 new ones over 3 years)
changed out lighting (bought new bulbs)
added more live rock
manual removal (siphoning)
decreased photoperiod (shortened time)
changed photoperiod (MH off, only actinics on)
ceased photoperiod (covered entire tank with blanket for 2 days, works but will kill some corals)
changed sandbed and restarted tank (from aragonite to oolitic)
Thing I did that was finally successful (IMO):
powerwashed rock and left in dark for 1.5 weeks
restarted tank as barebottom
I fought dinoflagellates for the better part of almost 3 years, I have no idea what I was doing wrong but from May 2004 to May 2005 I had a cyclical invasion of dinoflagellates approximately every 6-8 weeks, nothing I did killed them until I finally tore the tank down and removed the sandbed. Sometimes doing something major to the tank can shock them and kill them, other times not.
Good luck dude, you'll need it.