<a href=showthread.php?s=&postid=15441995#post15441995 target=_blank>Originally posted</a> by PhreeBYrd
Before proceeding, I would strongly recommend testing both the tank water and your new seawater for nutrients - definitely for nitrate and phosphate, and probably for ammonia and nitrite as well. Something is definitely feeding the algae growth.
Darkening the tank can knock the algae back somewhat, but won't kill or eradicate it (it will also take at least 4-5 days to even begin to have a noticeable effect). A lawnmower blenny will most probably not be very interested in your GHA. We have found that AlgaeFix is rather specific in the species of algae it will be effective towards, and some users, including myself, have reported negative affects on inverts (mostly snails) and some corals (mostly sps). I'd recommend having your GHA positively identified (I'd think somebody at UCSB, USC, or UCLA can help with that) to see if AlgaeFix is even a worthwhile option.
Among those for whom AlgaeFix has worked, most have seen positive and quite definitive results by the 4th to 6th dose. AlgaeFix is definitely not as reef safe as we might be led to believe, particularly once we get up beyond 10 or so doses.
That might indicate that if you're not seeing very definite results by 6-7 doses, then it would be prudent to halt the treatment.