Yes they do need a filter. People often think they can live with no filter in small bowls, this is not true. Goldfish are very dirty fish because people often overfeed them so make sure you have a filter.
If you have a goldfish you have a Goldfish you should also have a tank at least 10 Gallons. If you have more than one fish with your goldfish or have lots of goldfish you need an aquarium larger than 10 Gallons so that all the fish have lots of room to swim. If your fish have no room to swim and have no filter they may be on there way to dying.
It is unwise to try to keep any fish in a tank with no filter and goldfish need one more than most. The job of a filter is not to filter out the visible dirt as many people think. Its job is to biologically convert the ammonia that is produced by the fish living, breathing, pooing etc in the water. (This ammonia is deadly poisonous to all life including fish). The filter uses naturally occurring aerobic bacteria on the filter media to convert the ammonia into relatively harmless nitrate.
Goldfish filters need to be on all day and night. Goldfish are the messiest fish around so do NOT keep it in a bowl. Besides filters also help provide oxygen.
They don't have to have one but it's better for them and they will live longer if you do.
Goldfish can not get pregnant they are egg layers and their eggs are fertilised externally. Never turn filters off on a fish tank unless you are cleaning them. Cycled filters are needed to remove the poisons from the water that the fish create by living/pooing etc in there.
That you need a new goldfish
How you would care for an ordinary goldfish, feeding, cleaning, changing water, check filters, temperature gauge, pump and look for signs of ANY infections.
Goldfish.
there are three basic breeds: fantail goldfish, comet goldfish, and common goldfish. if you are getting goldfish for the first time, i would recommend common goldfish as they need the least care.
The answer is no. People usually think that goldfish get lonely and depressed. This is not true. Goldfish are fine on their own! People usually prefer 2 or more
goldfish need to lay eggs. Because if they don't no goldfish would be alive and would not be any more so they would become gone forever.
Well the best thing to do first, when they have outgrown their little tanks, you should get those big tanks with filters. You should get a big one because it would give your goldfish a lot more room to swim.
Yes, goldfish are very messy. Goldfish need 10 gallons per fish, you actually need a 20 gallon tank or about a 70 liter tank for 2 goldfish. But the small tank will do while they are small, you will need to eventually get a larger tank.
Filters are beneficial for any aquatic life.