Complex sentence: Some of the tags we will use are buoyant, brightly coloured, and carry a reward/return label they will float to the sea surface and some will eventually be washed ashore where they may be found by members of the public and returned.
Split into simpler sentences: Some of the tags we use are buoyant, brightly coloured, and carry a reward/return label. They will float to the sea surface and some will eventually be washed ashore where they may be found by members of the public and returned.