I have recently bought two goldfish with a standard tank, say 30cm x 20cm. They are a comet and a shebunkin(?)
I have recently noticed that the fish are often swimming to the top for a few minutes at a time and then going back down. Through doing some research, i think that this is because I dont have a filter and the fish do not have enough oxygen.
Can anyone help with any advice? Also, what type of filter would be best for me? Thanks
I have recently noticed that the fish are often swimming to the top for a few minutes at a time and then going back down. Through doing some research, i think that this is because I dont have a filter and the fish do not have enough oxygen.
Can anyone help with any advice? Also, what type of filter would be best for me? Thanks