Mechanical removal is about your only option. Take a look at this thread for removing duckweed. Same principle, it should work for your algae.

https://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=35775


www.hoosierpondpros.com


http://www.pondboss.com/subscribe.asp?c=4
3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).