Because there getting used to there new surroundings
Maybe your tank is not properly filtered and its water is bad. Are you following the basic rules of fishkeeping. " 1 inch of fish needs at least 1 gallon of water. (A goldfish is a 10 inch fish) Every tank must have a permanently running 'cycled' filter. Every tank must have at least 50% of its water replaced every week.
no. you should have 10gal of water per goldfish. you shouldn't have goldfish in a 5gal tank at all. they are huge waste producers
The reason why the goldfish is at the bottom of a fish bowl is because it is dead. (edit) It may also be resting. Fish do this from time to time. If it doesn't swim about at all, then it's probably dead though.
It depends, if the goldfish are all males (or females) no, but if not of course they can mate.
I used to have snails with my goldfish and they got along swimmingly!
I had an albino plecostomus hang out in the bottom of my goldfish tank. He thrived quite happily with my comet and fancy goldfish. The only thing you have to be careful about is the ammonia levels can't get too high. Adding an ammonia filter to your water filter can help reduce the levels, too. I also had to give him algae supplements every week or so because he kept eating all the algae that built up. If you don't mind another large fish to add to the tank, dojo fish are also good bottom feeders.
Usually it's because the male wants the breed with the female so he chases the female around the tank! So unless you want little fry (baby goldfish) in your tank you should separate them!
Bubble eyed gold fish have to stay at one spot in the tank because they feel like they rule the tank kind of thing and they want to watch all the other fish
There are several species of fish that are known to make bubbles. These include bettas, Siamese fighting fish, and goldfish.
The water is pumped for a certain time, as the water is pumped from the bottom tank to the top tank and we get our water for the day from the top tank only.
If you are talking about such a small tank that the fish is touching all sides at the same time, then yes. But if you are talking about a little goldfish in a 15cm x 15cm tank then no, it will just be a bit uncomfortable.
Depending on what your sick goldfish has, it will either be specific to that fish, which you should place in a separate tank to treat, or it's something that will spread to other fish in your tank, in which case you will need to treat them all.