Yeah, I’ve had similar experiences with DIY stuff like this. Yogurt never really quite worked for me. Kefir was good as long as I used the powdered starter (which you can only reuse a few times), not the real deal kefir grains which never worked for me. I think I’ll stick to buying the Synergy Guava Goddess kombucha but only when it’s on sale! It was 2 for $5 at my local grocery store last week so I treated myself to two bottles.