HomeCompare fishCrescent betta vs Siamese fighting fish Crescent betta vs Siamese fighting fish: can they live together? Verdict: With cautionThe Siamese fighting fish can be semi-aggressive or nip fins.Both are comfortable at 24–30°C (75–86°F).A pH of 6.0–7.0 suits both.Minimum tank for the pair: 40 L (11 US gal)Side by sideCrescent bettaSiamese fighting fishAdult size6 cm (2.4 in)6.5 cm (2.6 in)Minimum tank40 L (11 US gal)20 L (5 US gal)Temperature24–30°C (75–86°F)24–30°C (75–86°F)pH6.0–7.06.0–8.0Hardness5–19 dGH (89–339 ppm)5–19 dGH (89–339 ppm)TemperamentPeacefulSemi-aggressiveCommunity tankGoodGoodCare levelEasyEasyDietOmnivoreOmnivoreSpecies profilesCrescent bettaBetta imbellisSiamese fighting fishBetta splendens