Since I've started in January, I've been using the Petco Ocean water for startup and water changes, topping off with distilled. Just wondering if most people with nano's are making their own RO/DI (and what unit for nano needs), buying RO/DI and mixing their own, or using ocean water. Does anyone have experience with all types and have noticed if one is better than another? I'm having good luck with Petco's Ocean Water, but lugging 5 gallon boxes from the store, to the car, to the house, upstairs, into the tank...is a bit of a hassle. I'm wondering if I should just consider it a workout, or if there is a better path of least resistance.