if you get a filter with an 'in line' uv light that helps to kill the spores of this dratted nuisance. the other thing you can do is use a stick and wrap it round and keep removing it. do you have plants in the pond? if yes make sure you use a low feed specially formulated compost for aquatics or just plant them in washed gravel. excess nutrients in the water will feed the blanket weed.

A hair brush tied to a broomhandle will help to remove it, leave the weed on the side for a while to let the pondlife escape
My koi carp eat it.....