piping

Hello, I bought a EHEIM ecco pro 300 External Filter waiting for delivery, The Eheim site says for the ecco pro 300 - Hose Ø Suction side(inside) 12.00/16.00 mm, I am buying a Hydor ETH300 External Heater that says it has inlet hose 16mm, Connects to 16mm & 5/8" Hose. Sorry it's a daft...