Ice Guard What is this? will probably be your first reaction. Which proves that simplest is often best. This plain-looking block just needs to be dropped into a pond or pool and will prevent solid ice forming. And it has a secret surprise: as well as making sure your fish get oxygen it has a hidden compartment underneath for frogs to take refuge. Winner of a UK Wildlife Trusts Award.
Needs at least 4 inches of water to float.25cm high
