Practically any pet store.
Filter a fish? Do you mean filtering a fish's tank? Well you have to filter any fish's tank.
You can buy a livestock water tank and a filter and that works fine.
Yes you do need a filter in your fish tank ifyou don't the tank will build up dirt and the fish will die. Also when you get a fish tank you need to clean it out then fill it with water then put the filter in and wait 24 hours. This helps to ensure that the tank is somewhat stable before adding fish.
You should probably find them a new home and when the time comes to have fish again, you should buy a bigger tank and a filter. Three fish cannot properly live and survive in a 2.5 gallon tank - this is not even safe for a betta
no - never buy a fish from a tank with a dead one in
The filter removes the fish waste and some of the other impurities.
Umm you could buy a fish tank and put it in your room just make a fish then buy a fish it will get in side the fish tank in your you don't have to do nothing just buy a fish and a fish tank and it is put in your room
Then your filter is not on.
A filter...
no filter because for smaller fish it can hurt or even kill them and for the old filter use bigger fish
yes
Yes