emmajt
Fish Fanatic
I have a recently established tank tropical tank (fishless cycle completed last week) the tank now has fish in.... Until my mother came home with a goldfish from a hen party (random, something to do with bridesmaids film apparantly?) so I had to buy a new tank (60l), now I need a new filter for this tank but I was thinking of getting a external for my tropical tank and giving the established filter to the new tank? How do I do this without upsetting the water in the tropical tank that is already established with a new external filter in place wont I lose all the good bacteria?