1 kinds · tap one for a closer look
Aggressive predator; keep alone or with large robust fish.
Shops sell a "marbled oscar" that is just a colour form of the common oscar. This page is Astronotus crassipinnis, a different species from the Paraguay basin.
This one is best kept on its own, or with its own kind.
Aggressive predator; keep alone or with large robust fish.
Large pellets, prawns and live insects. Avoid feeder fish.
Tap a food to see what it is.
Common problems. Tap one to see the signs. This is a guide, not a diagnosis.
Open substrate spawner · Moderate
Substrate spawner with parental care.
Grow out 6 juveniles and let a pair form; separate the pair if others are harassed.
A 400 L tank with a sponge or gentle filter, flat slate or rocks as spawning surfaces and a tight lid.
Warm, clean water, frequent water changes and protein-rich food.
500-1000 eggs
Parents move the wrigglers to pits and guard the free-swimming fry; feed newly hatched brine shrimp and crushed flake.
A rarely kept oscar from the southern Amazon (Guaporé/upper Madeira) and upper Paraguay basins, sometimes called the 'fat oscar'. Its body is very dark, almost black, and it lacks the eye-spots at the dorsal-fin base that mark the common oscar. Often mistaken for the common oscar.
Heckel described this oscar in 1840, but for a long time all oscars in the hobby were simply called Astronotus ocellatus. Scientists now recognise crassipinnis as a separate species with a range further south and west. It is as large and personable as its famous relative.
First described by Johann J. Heckel in 1840.
6 facts checked with sources
Valid. Glaser labels its Rio Paraguay imports 'A. cf. crassipinnis' because only Guaporé fish are certainly this species. Naming caution: in the trade 'marbled oscar' and 'tiger oscar' usually mean colour forms of the common oscar A. ocellatus, and Wikipedia says A. crassipinnis is often mistaken for it. Suggest the site use 'Paraguay oscar / fat oscar' and drop 'marbled oscar' as an alias.
FishBase: Astronotus crassipinnis summary · Aquarium Glaser (Schäfer) 2016: Astronotus cf. crassipinnisLegacy has no family field.
FishBase: Astronotus crassipinnis summary24 cm SL is the largest sourced figure (FishBase common length 25 cm TL). Glaser: it 'seems to stay a bit smaller than A. ocellatus'. Legacy 30 cm is above all sources, though a 24 cm SL fish is close to 30 cm TL.
FishBase: Astronotus crassipinnis summary · Aquarium Glaser (Schäfer) 2016: Astronotus cf. crassipinnis · Wikipedia: Astronotus crassipinnis (cites FishBase)No source names a swimming level.
FishBase: Astronotus crassipinnis summaryLegacy has no range field (story says Río Paraguay basin only).
FishBase: Astronotus crassipinnis summary · Wikipedia: Astronotus crassipinnis (cites FishBase)Legacy 'marbled pattern' and 'Río Paraguay basin' are only partly right: the range includes the southern Amazon and the key marks are the dark body and missing dorsal ocelli. 'Hardy' is unsourced.
Aquarium Glaser (Schäfer) 2016: Astronotus cf. crassipinnis · Wikipedia: Astronotus crassipinnis (cites FishBase)