Phalloceros caudimaculatus is a livebearing species known from densely vegetated streams and ponds, as well as the sluggish sections of rivers. They prefer a heavily planted aquarium with gentle filtration and water movement, in order to emulate the natural conditions. Choose robust plants or fast growers, as many soft leaved plants will be browsed upon, although not so much if the fish are kept well fed. Floating species such as duckweed (Lemna spp.) may be used to help diffuse bright lighting. Wherever possible, it is best to keep at least 2 or 3 females to every male; this will reduce the amount of attention that any one female receives from the amorous males and will also further your chances of raising more fry. A shoal of at least 6-8 fish is preferable in a good sized tank, and although there may be a bit of minor chasing between rival males, they are rarely aggressive towards one another and generally do not cause damage. Tankmates are possible, but do ensure these are short-finned, fast-swimming, and are happy in the same cool conditions - although be aware that in such a community setting, any P. caudimaculatus fry may be at risk from predation. Some wild populations of this species inhabit mildly brackish conditions, and although most that are offered in the trade are captive bred in freshwater, it is wise to check with your dealer what conditions they are being kept in. These fish are very sensitive to changes in water chemistry, so any adjustments in parameters must be carried out gradually, and much care should be taken when performing water changes (change very small amounts on a frequent basis, but add the new water very slowly). For this reason, we would suggest this species for advanced aquarists only. The natural colour form of P. caudimaculatus is a rather plain silvery fish with a small, dark, vertical elongated mark under the dorsal fin origin, and profusions of black patches on the fins. However, there are several tank bred colour forms available in the trade, which have been assigned erroneous scientific names that are not actually valid, but are mentioned here as they are so widely used. These include the spotted form P. caudimaculatus 'reticulatus' (pictured here), a golden variety known as P. caudimaculatus 'auratus', and a spotted, golden form referred to as P. caudimaculatus 'reticulatus auratus'. The pictured fish were captive bred in the Czech Republic. The wild form of this species was deliberately introduced to Ethiopia, Malawi, Australia, and New Zealand in efforts to help control mosquito numbers. The fish have become firmly established in these countries, yet unfortunately have had negligible effects on mosquito numbers, and in some areas have actually had adverse effects on local fauna.