The Koi betta is generally known as the Marble betta and is actually a shade morph on the familiar and universally well known betta splendens. The Marbled Hatchetfish you presently locate while in the trade are wild-caught, so we propose quarantining them before introducing them to your most important tank. https://freshwaterfish.travel.blog/2024/04/14/how-to-keep-a-pond-cleaner/