red algae

Are you talking about cyanobacteria, or red turf algae? I'm guessing cyano. That can be tough to get rid of, because you can have no N or P and still get it, it creates it's own source of N. Cyano doesn't like flow, so increasing that can help. Physical removal through siphoning can help, but the stuff sticks onto rockwork and gravel, so you usually have to siphon the top layer off of gravel and remove rock and scrub it with a stiff brush, which can be difficult or impossible with coral attached. Generally you have to attack it from all angles. I beat it by doing PWCs, physical removal (several times), running a diatom cartridge on a canister filter, changing filter socks frequently, make sure your skimmer is running right, reduce feedings, change your light bulbs (if you haven't done that lately - light shifts to red over time, cyano likes red light), and reduce the light cycle or you can do a total blackout for 3 days if your tank can handle it, run carbon, run Purigen. There is also a chemical treatment you can get at Seascapes, Chemiclean I believe that is supposedly reef safe. But you need to get to the root of the problem and fix that first.

 

No, in fact there are certain snails that you want to add. I left that out. I added a ton of Nerite snails, dwarf cerith snails (small, get into crevasses), and nassarius vibex snails also. I got them from http://www.reefcleaners.org/ I highly recommend then BTW.

 

Yeah they're great algae munchers, in China Garden's tank, you could watch day by day as they plowed through the algae on the overflow towers. In 2 weeks it was gone.