I bought a 5.5 gallon fish tank (which has a filter) and filled it with spring water. I filled it with 2 fancy guppies, 2 red wag platys, and 2 black skirt tetras. I got everything put together yesterday and stocked my tank with the fish. The water was clear and there was no smell. I fed my fish yesterday and realized today that there is food leftover. It was today when I noticed the water stated to become a bit cloudy. About 2 hours after this I started to smell something that smelt like garbage and realized it was the fish tank. This smell went away until I had to feed my fish. Now the tank is even more cloudy (I can barely see in it) and it smells again. What do I do???