Hehe there's no surefire way to keep this worms alive for a long period. Tried many times previously during my other fish heydays. Temperature must be low. Must have some mulch for them to dig in. Water changes. Suprisingly these fellas can live in the drain/sewer but just not your container. To me feeding tubi has too many downside. Not worth it for delicate fishes. But anyway for growth tubi definitely champion.