Pond filtration for home use ponds

Just curious as to what I should do to filter the water that comes in from the pond and supplies everything but the drinking water. We just bought a house and Im a usual city dweller so this country business is new to me. Inside the toilets tank is what has me worried, its caked with grime Id assume is from the source. Id like to avoid having to scrub the toilets and sinks all the time and think something filtering that would prolong my washer and dishwasher. Just curious if anybody has any expertise to share, any will be more than I currently have.

When you say grime, what does it look like? Typically when a house is on well water, water softeners should be used to remove a lot of the minerals which cause calcium buildup and what not. In municipal areas, the water company takes care of this.