This section contains fish which are often sold for the community tank, but which may cause problems for
various reasons. They should be considered carefully in relation to other fish in the tank, tank size, etc.
Click on the links for more info on individual fish.
|Species||Notes: reasons for classing as 'with caution' fish
|Although normally peaceful, individual fish are sometimes aggressive. Spawning pairs will also be very
aggressive towards tankmates. They grow a bit large for smaller community tanks and a 24x12x18" tank is probably
a good minimum for a single adult. Adults may also eat small tetras which are subsequently added to the tank.
(Trichogaster, Colisa, etc)
|Often included in community tanks, but often territorial and can be quite aggressive, particularly with
other gouramies or similar fish. Some species grow quite large.
|Red-tailed black shark
|Very aggressive and territorial with others of their own kind (or similar). May also be aggressive with
other fish. May become more aggressive with age.
The silver/bala shark - a large shoaling fish that requires plenty of room.
Tiger barb - a possible fin-nipper.
|Prone to fin-nipping behaviour, see comments below for Tiger barb.
|Can grow very large (up to 14"/35cm, though more often around 6-8"/15-20cm) - they are also active swimmers, and therefore need
a large tank (do not consider less than a 3-foot (92cm) tank for juveniles, larger adult fish will need a bigger tank). Tend to be nervous and jumpy
- may injure themselves.
|An active and colourful barb, but one which may nip the fins of other fish, particularly slow-swimming fish with
long trailing fins e.g. angelfish, guppies, male Siamese fighters/Bettas. Other fish may also be nipped. The fin-nipping
behaviour is usually reduced or eliminated by keeping the fish in a shoal (at least six recommended).