String algae blanketweed can be a real problem in late spring summer. This new solar ioniser from pondhero tackles this problem quickly and effectively! as it is solar powered you simply need to float the unit on the surface of your pond and it will do the rest on those sunny days. It is designed to release copper ions into the water which effectively bind themselves to the pond's contents, preventing algae growth as a result.the set contains a blaster unit, test strips and a brush.note excess copper ions are dangerous to pond life so you must follow the following operating advice• not safe for sturgeon br • not recommended for fish ponds unless monitered carefully br • use when pond water is at least 12°c br • remove from action when weed has been removedthe hanna digital copper tester can assist with checking the copper levels in your pond.