Pump for filling aquarium

[Navigator]

Okay, I'm really clumsy with buckets, so I have decided in the interest of NOT having another accident with water (especially salt water) I would like a pump that I can use to transfer from my big mixing Rubbermaid to the tank after water changes and probably also for fresh water top ups.

I obviously need a pump that is okay with salt water - and that seems to be hard to find. I tried a sump pump from Princess Auto - Not Good. Too much flow. Since I don't need to really do anything fast, I tried their little drill powered one - complete fail. Help, please? Pumps are one of those things that have always mystified me!