If that's one of those internal filters, then yes, you could use it in your saltwater make-up bucket (without the sponge). Really, anything that pumps the water is fine.
Some pumps put off more heat than others, so you'll really just have to see how it goes with the water temperature in the bucket.
It's so hot here that I only use a heater in the bucket for a month or two of the year. I forget that it's not always that warm in people's houses.
