HomeCompare fishFlame tetra vs Black neon tetra Flame tetra vs Black neon tetra: can they live together? Verdict: CompatibleBoth are comfortable at 23–28°C (73–82°F).A pH of 5.8–7.5 suits both.Minimum tank for the pair: 75 L (20 US gal)Side by sideFlame tetraBlack neon tetraAdult size4.5 cm (1.8 in)3.2 cm (1.3 in)Minimum tank55 L (15 US gal)75 L (20 US gal)Temperature22–28°C (72–82°F)23–28°C (73–82°F)pH5.8–7.85.5–7.5Hardness5–25 dGH (89–446 ppm)2–15 dGH (36–268 ppm)TemperamentPeacefulPeacefulCommunity tankGoodExcellentCare levelDifficultEasyDietOmnivoreOmnivoreSpecies profilesFlame tetraHyphessobrycon flammeusBlack neon tetraHyphessobrycon herbertaxelrodi