I am having problems with red cyano and hair algae in my 30g tall that have 5 erectus. I do a 5g water change every week. I currently have a emperor 280 and one ph that occilates in front of the sea fan. I get cyano on the horses and behind the fan and certain places on rock. My question is would an emperor 400 be too much flow? I am hoping the extra flow would help and I really do not want to add a skimmer on this tank. I do not have enough room for a fuge either. I already have some phosban in the filter to help. I feed twice a day (mysis) which is contained for the horses.