I imagine you are asking if you can keep goldfish with other freshwater fish. And the answer is; yes and no. Most freshwater fish prefer to be at a higher temperature (around 80F) whereas goldfish prefer around 65-70F. It usually doesn't work out very well, but it doesnt mean that its impossible.
Feeder fish should be cared for in the same way you would care for any other freshwater fish if you choose to keep and raise them
It depends on the fish. If its a tropical fish that is accustomed to salt water, you need salt water and you need to keep the water at a warmer than norm temperature. If its just a regular goldfish, freshwater at room temp should do just fine.
Yes. They are both freshwater tropical community fish and should get along well.
The temperature of the water depends on the type of life/fish you intend to keep in the aquarium.
It's the freshwater fish. In the U.S. people keep 142 million freshwater fish in their homes. There are 88.3 million cats and 74.8 million dogs.
None. A single goldfish should have a minimum of 75L. You would be better off keeping small tropical freshwater fish.
There are many freshwater tropical fish. In fact most of the tropical fish kept by aquarists are freshwater and they can not survive in either cold water or marine (salt) water. In most cases the marine species are much more difficult to keep and much more expensive to set up for.
Usually. Most fish dont pay attention to baby fish, they will usually eat them, as far as freshwater fish, I know that you can keep Betta fish male, Plecostomus, and Chicleds with there babys.
i have absolutely no idea. why would someone keep piranhas? no offense. they are kind of cool
There are a variety of fish that can keep a tank clean. The type of fish will depend on the type of aquarium setup. In a freshwater tank, different types of plecostomus are most common.
about 85F