Recommend water pump

[Rexxer]

Hi I have a 3ft Ranchu tank running on Mr Aqua stackable ohf with 8 trays. I am currently using rio hf8 pump. The flow is ok but I find that the pump is getting very noisy, especially at night when its quiet at home.
Can anyone recommend a pump that is quiet and is enough to support my ohf? Is it better to run the pump externally so that there's more swimming space for the fishes?
Cheers

[Rexxer]

No experience bro can advise?