I have a 68L tall and narrow hexagonal tank. It was supplied with a top mounted external filter - basically a long narrow box mounted in the lid fittings - with a long inlet pipe that served pretty well, but the motor just packed up. It was rated at 450L/h

I can get a replacement pump motor but the one I'm replacing is discontinued and the dimensions of the new motor are slightly different so I will have to do some sort of bodge-it job to mount it and I am worried about rattle. I'd also like to consider a filter upgrade to provide more filtration and a higher flow rate if possible.

Because of the shape of the tank 100% internal filters aren't ideal because of the amount of space they take up. The pic shows the temporary filter I've put in until I have a better solution. As you can see it takes up too much space.

I was looking at HOB filters but the lid design makes those problematic. Canister filters would be OK but the tank is on a kitchen worktop so hiding the canister would be a challenge and therefore isn't ideal.

I haven't been able to find any top mounted filters similar to the one I'll be replacing.

Has anyone any suggestions, before I just bite the bullet and get the replacement pump motor?