HomeCompare fishForktail rainbowfish vs Black ghost Forktail rainbowfish vs Black ghost: can they live together? Verdict: Not recommendedThe Black ghost is aggressive towards other fish.An adult Black ghost is about 10 times the length of a Forktail rainbowfish and may eat it.Both are comfortable at 24–26°C (75–79°F).A pH of 6.0–8.0 suits both.Side by sideForktail rainbowfishBlack ghostAdult size5 cm (2 in)50 cm (20 in)Minimum tank75 L (20 US gal)210 L (55 US gal)Temperature24–26°C (75–79°F)23–28°C (73–82°F)pH6.0–8.06.0–8.0Hardness5–12 dGH (89–214 ppm)5–10 dGH (89–178 ppm)TemperamentPeacefulAggressiveCommunity tankGoodGoodCare levelEasyModerateDietOmnivoreOmnivoreSpecies profilesForktail rainbowfishPseudomugil furcatusBlack ghostApteronotus albifrons