I have been trying to breed water with lightning and I never get a storm dragon. Any clues on how to make this happen

My dragons are lvl 6 and I breed in the mountain. I have like 10 lanters

Actually you're doing it right, though different combos have different chances of success, keep trying or use any of the other available combos if you can/want: https://dragoncityguide.net/how-to-breed-storm/