I bought a Fluval 303 canister filter for 10$. It is in great shape, had very little cleaning to do on it. The reason it was very clean and very cheap. Is the fact it is missing a very crucial part to make it run. It is missing the impeller cover A15820 is the part number. I understand it is a old style filter. But it seems the replacement parts are no where to be found. I even contact Fluval Head office in Canada and no go. If anyone has a used one or broken one. Hit me up and we can arrange something. Thank you.