Please help with my scolyscoly

[BC1906]

I purchased this scoly a couple of months ago. It has been doing great until recently. It is starting to recede and shrink.

Temp- 78
Sg- 1.026
Ph- 8
Amn-0
Nitrite- 0
Nitrate-5ppm
Phos- 0
Cal- 480
Mg- 1200
Alk-8.1

Lighting is a hydra twenty-six HD running at 50% blues and about 20% white from 10am-9pm.

I have been dealing with an algae issue as you can see so I'm not sure if that is contributing to it. My other corals except for 1 acan are doing fine.

Here is a before and after:

 

[mcmunn93]

Looks like algae is taking over
Try removing the algae be careful though

 

[mmw64]

following with interest

 

[X.M.Chen]

Take care the algae I think you will be fine. But you have to solve it quick. I will do 25% water change once a week.

 

[BC1906]

I'm trying to get the algae under control. My tank is a biocube 29 and I do weekly water changes of 5 gallons. I'm running an Aquamaxx HOB-1 skimmer with chemi blue, deep blue phosphate pads and some filter floss. I just bought another powerhead and grabbed about 12 hermit crabs, 9 trochus snails and a lawnmower blenny to try and get it under control.