green hair algae and prognosis

today it is especially thick. it started off as the size of a fist and is now about 14" long.

is this GHA or do i have something more serious going on?


i replaced my GFO two days ago in case it was time, i tuned my biopellet reactor off in case they were clumping and causing an outbreak. i change 35% of the water every week, feed half a cube and some cyclops for my 46g and four fish once a day, phosphates are reading .02ppm and nitrates/nitrates at 0ppm. light is on for 10 hours a day.

any idea on what it is and how to get rid of it or what i'm doing wrong?

#1 Manually remove as much of the algae as possible.

#2 Cut WAY back the feeding.
With 4 fish a half cube should last a week if your feeding every day. But don't do that either. Feed no more than a 1/4 cube every other day.

#3 Get more flow in there.Don't know how much you got now,but more will help.
with removing it, there isn't a concern for disturbing the sand bed? removing it would definitely agitate the sand bed.

and half a cube lasting a week for 4 fish?!! really?wow. I feed a cube a day sometimes plus spot feeding the corals. I try to feed smaller meals three times a day instead of one large meal. I guess that's my problem bit this is the first time with this issue in about five years.

sorry I forgot flow. the tank is pretty open and that area receives excellent flow. I have two mp10s and a 400gph overflow.

and is this GHA?

thanks for the advice!
Don't look like it to me. But could be I guess.

Yeah,Your probably gonna disturb the sand a little.But one thing that makes algae hard to kill,is as it dies,it releases all it's stored up nutrients right back into the water.So it's easier to get the algae out then address the cause of it.

On the feeding.
My tank went a full year without me adding ANY kind of food to the tank.When I broke it down,the fish and corals was as fat and healthy as anybodies.
What happens with fish,is they'll actually eat until their passing the very nutrients they are trying to get.They'll eat as long as the food is there.So all those extra nutrients are going straight into the water.
ok, i'm gonna go remove it. i'm starting to get small light green spots in other sections of the sand bed so i really don't know what it could be. perhaps the overfeeding like you mentioned.

your story is very interesting - so what were your fish eating if not food you provided?
The natural algae that grows in all marine environments for the tangs.The rest ate the copeapods and amphipods.
People tend to forget that in the wild ( and 99.9% of marine fish are wild caught ),the reef provides the food the fish need to live. So with a little research and planning,you can have a self-sustaining reef.Makes for very easy maintenance.