HomeCompare fishGlass knifefish vs Pirapatinga Glass knifefish vs Pirapatinga: can they live together? Verdict: Not recommendedThe Pirapatinga is best kept in a species tank.The Glass knifefish is best kept in a species tank.The Glass knifefish is aggressive towards other fish.The Pirapatinga grows about twice as long as the Glass knifefish; watch for bullying or predation.Both are comfortable at 23–28°C (73–82°F).A pH of 6.0–6.8 suits both.Side by sideGlass knifefishPirapatingaAdult size35 cm (14 in)88 cm (35 in)Minimum tank210 L (55 US gal)–Temperature23–28°C (73–82°F)22–28°C (72–82°F)pH6.0–7.54.8–6.8Hardness2–15 dGH (36–268 ppm)4–15 dGH (71–268 ppm)TemperamentAggressivePeacefulCommunity tankNot suitableNot suitableCare levelDifficultEasyDietCarnivoreHerbivoreSpecies profilesGlass knifefishEigenmannia virescensPirapatingaPiaractus brachypomus