My tank gets cloudy every three days am I supposed to clean it that often or do I need anoother filter. I have four Large comets in a 10 gallon tank.

Hello Jennibrown,
The best thing for your fish would be a larger aquarium;
However in the meantime adding another filter is a good idea.
Goldfish produce a lot of waste and need excellent filtration and lots of room.

It sounds like your aquarium is trying to establish its cycle.
The cloudiness in the water is caused by a bloom of beneficial bacteria.
It will clear up on it's own, but it does take time.
Once it clears, be very careful not to over clean the tank or filters.
Too much cleaning removes too much of this good bacteria and the
Cycle will have to repair itself which will again cause the water to cloud up.

Please read Aquarium cycle/Nitrogen Cycle (https://www.askmehelpdesk.com/other-pets-animals/aquarium-cycle-nitrogen-cycle-77553.html) to understand the process
Your tank is going through.

Since you have large goldfish,
Adding another filter will really help the aquarium cycle.

Happy fish keeping

There is a type of magnet that one half goes into the fish tank and the other half is outside. You move the magnet from the outside and the other half cleans the glass or plastic.