Honestly, I wouldn't worry about the shape of that bowl, but I wouldn't use it for water for a snake anyway- it's designed for rodent- hamster- feed (which is dry!), & might be less than safe with water constantly in it for a snake to drink. Ceramic pet bowls are coated with a glaze which may contain lead, or once the glaze gets fine hairline cracks in it- which is common- lead or who knows what else can leach out of the ceramic & into the water your pet drinks. Products made for pets often don't get the same scrutiny for safety that products intended for humans do- just saying. You'd be better off with an old (or 2nd hand) glass mixing bowl (or casserole dish, for example). It doesn't matter why he dove into the bowl, I don't think he was in serious danger of drowning.