We installed two ponds last year complete with electronic blanket weed
controllers. They worked very well.

This year we have had blanket weed in the small pond throughout most of the
summer and is now becoming established in the large one. Nothing else has
changed.

Does anyone have any experience of the blanket weed controllers, how
successful they are? How can we tell if they are workign (other than via the
flasing lights which appear to be OK).

Many thanks