Can i put a betta fish with a goldfish in one tank?
No it won’t work. BUT not for the reasons others have stated. A Betta is unlikely to be able to kill a Goldfish unless said Goldfish was exceptionally small and already weak. What’s more likely is the Goldfish kills the Betta! There’s also the issue that Goldfish are HUGE fish needing very large over-filtered coldwater tanks, at around 65-72F max. These tanks are likely to have too much current for a weak-swimming Betta and you wouldn’t be able to heavily plant it as Goldfish eat plants, and the mess Goldfish make could increase ammonia if your not careful, killing the Betta first. And a Betta in coldwater = a sickly, lethargic and depressed Betta. That and a large Goldfish could easily eat a Betta. Bettas need WARM tanks, at 78-80F, not suitable for Goldfish at all. They need dense planting (real plants are best) with some touching and breaking the surface and very little current as they are not strong swimmers. So no, they can’t be kept together.
