Why do I have hair Algae

[ScottyD36]

I have a pretty good concept about hair algae. I have a 40 gallon CVUE tank. It’s about a year old. Everything in my tank is healthy from fish, CUC and corals. I have one side the left side of my tank that is just getting hammered with hair algae and it’s starting to spread. Normally my CUC crew would eat it all up and it wouldn’t be a issue but for some reason nothing is touching this side of tank. My parameters are as followed in the picture. I have to bring down the phosphates. But what is some CUC crew everyone has used to eat up hair algae. I have a pretty diverse CUC currently. I even took one of my urchins out of time out (was eating Zoas) to try and combat. I have used peroxide before on my nano tank but I don’t want to go down that road.
Temp-77
PH - 8.1
Alk - 11.5
Calcium - 414
Mag - 1176
Phos - .32
Pictures are of my tank and compared sides. Thanks for any advice.

 

[CanuckReefer]

I have a pretty good concept about hair algae. I have a 40 gallon CVUE tank. It’s about a year old. Everything in my tank is healthy from fish, CUC and corals. I have one side the left side of my tank that is just getting hammered with hair algae and it’s starting to spread. Normally my CUC crew would eat it all up and it wouldn’t be a issue but for some reason nothing is touching this side of tank. My parameters are as followed in the picture. I have to bring down the phosphates. But what is some CUC crew everyone has used to eat up hair algae. I have a pretty diverse CUC currently. I even took one of my urchins out of time out (was eating Zoas) to try and combat. I have used peroxide before on my nano tank but I don’t want to go down that road.
Temp-77
PH - 8.1
Alk - 11.5
Calcium - 414
Mag - 1176
Phos - .32
Pictures are of my tank and compared sides. Thanks for any advice.

I'm wondering if it's all related to flow being that its on one side only? How are your pumps and wavemakers etc positioned? Or is that side suffering light in any manner? The Phos is high, but not sure thats it being in only one section of tank....interesting....

 

[ScottyD36]

I'm wondering if it's all related to flow being that its on one side only? How are your pumps and wavemakers etc positioned? Or is that side suffering light in any manner? The Phos is high, but not sure thats it being in only one section of tank....interesting....

I have two Prime 16HD. They are split equally in tank. I have the one power head going to the right. My two pumps heads are facing left and right. Flow goes around that area its not a dead spot. The weirdest part is I can literally put my urchins right on top of the spot along with other snails and stuff and they just ignore the algae all together but rest of my tank is fine. Its one of the craziest things.

 

[CanuckReefer]

I have two Prime 16HD. They are split equally in tank. I have the one power head going to the right. My two pumps heads are facing left and right. Flow goes around that area its not a dead spot. The weirdest part is I can literally put my urchins right on top of the spot along with other snails and stuff and they just ignore the algae all together but rest of my tank is fine. Its one of the craziest things.

Wow....Time to bring in the experts @ReefSquad ....

 

[Cory]

Well .32ppm po4 will definitely grow some hair algae. Also sea urchins wont eat long hair algae, its gotta be short. Id suggest putting in 1 sea urchin per 50 gallons. Urchins are on the reef and when not in their natural numbers, hair alge takes over the coral reef. Algae removal is important to corals that algae growing on or near a coral (cms) will kill it through various bacterial processes being turbocharged by algae. Algae isnt bad but when it hits corals it kills due to in part sugars released. Once a big string of hair algae hit my birds nest and got tangled in it. Guess what happened? Yep rtn. Another time a birdsnest got a string of algae tangled in it from a glass scraping and died again! So yeah watch out for algae. Fwiw i grow turf algae on a waterfall ats and it is working so well im worried my sea urchins might starve in the tank! But they get pellets sometimes

 

[Reefahholic]

You should start to bring the PO4 down with a goal of under 0.1 ppm. Typically PO4 is almost always elevated by feedings if you’re not using tap water. Start to measure your feedings, Log them, and watch how the measured amount affects the PO4 level.

You could do several water changes while reducing feedings to get it down. I’d personally do about about 4x 20% spaced out 2-3 days apart. Each water change will bring it down by about 0.06 ppm.

You could also start running GFO at the appropriate dose with a faster flow rate (minimizing contact time) to slowly reduce it w/o shocking the system to much. Keep in mind that this will affect your light intensity.

Also, I noticed your Mag is very low. Bring that up to about 1280-1350. Also recommend to bring your Calcium back up to 420-430.

Good luck to you.