Some People say that carp will help with algea and scum.
I have a pretty large pond, and 4 years ago some people put carp in it. It helped cut down om lily pads, but the scum and algea remained and the carp eventually died. What ever treatment worked in the past will probably work now.
 Quote:
Originally posted by Meadowlark:
Grass carp (white amur) will help with the weeeds and Tipalia will attack the algae. I've found them to be a good combination that can reduce the dependence on chemicals for treatment.
Hope this helps you!
Refer to- http://www.pondboss.com/ubb/ultimatebb.php?ubb=get_topic;f=20;t=001678
and
http://www.pondboss.com/ubb/ultimatebb.php?ubb=get_topic;f=20;t=001526

-LUKE

All My Best Wishes for a boat-full,

Luke