Like most websites Reef One Ltd uses cookies in order to deliver a personalised, responsive service and to improve the site. Cookies are simple text files which sit on your computer, they are completely safe and secure and will never contain any sensitive information. By continuing to use the site you are agreeing to our use of cookies. Please read our Privacy Policy for more information.

Page cannot be loaded with reference: Popup Confirmation Text

number of fish in aquarium

Log in to submit a rating.

Not yet rated.

Your question

how many coldwater fish can i add to a biOrb 30

Our expert says

Introducing fish for Aquariums 30l – 45l

biOrb 30 litre,
biUbe 35 litre,
biOrb Life S30,
biOrb Life P45

You must resist the temptation to fill your aquarium with fish straight away. One small goldfish (1 to 1.5 inches) or three small shoaling fish (such as white cloud mountain minnows) can be introduced.

Wait at least 28 days before adding any more fish.

A gap of 28 days should be left between each addition of fish. Never add more than one goldfish or three small shoaling fish at a time. Buying too many fish at a time can kill the fish or at least make them very ill.

Fish Type

Each Month

Maximum Stock (biOrb 30)

Fancy goldfish
(basic fantails)



Small shoaling fish
(minnows, danios, etc)




If transferring fish from an existing aquarium to a new aquarium the fish must be moved over gradually as described above so that the aquarium can develop correctly.

Please Wait