Filter for koi pond waterfall

Hi all I've just moved into a house that has a koi pond with a waterfall type feature. The previous owner has taken the pump and other bits. I'm not planning on keeping koi but will get some goldfish. I have no idea where to start or what I will need to buy. Would this be suitable to filter and run the waterfall? https://www.amazon.co.uk/dp/B00WGMLMLQ... If so, what else will I need?