Nice pickup, I love the tiny guys. Keep it real, his survival rate at his size is about 30%, you sound like you're off to a great start. Everyone has already answered most everything, but think of it from his point of view, like how tiny and delicate he is. It's so easy to things to happen, but you're doing great. Keep him eating, don't feed anything to big or with hard parts that may block his intestinal tract. Keep him 80-83 degrees, clean water, an airstone, but a place where he can get away from current and rest. Try floating a plant on top so he can feel safe and rest. I always use a night light, and even tiny ones can jump out of the tiniest places. Best of Luck to you!