Brown scum

new job - almost stressed right out, sorry for lack of posts...
anyhow...

friends pond has a weird algae (i guess) that floats on top the pond - rusty brown colour
He put a filtering system in to fix it but its made no odds

Ideas?

A friend of mine had the same problem. They put barley straw in and it did eventually clear the pond and they haven’t had a problem since. It happened after they had planted new water plants and disturbed the sediment.

Concrete ponds are prone to brown algae, this is due to the high Calcium levels. It will sort it self out in time