A: Fill to max, place the panel in a sunny spot, and add a $8 auto-fill bottle (available in pet-supplies section) upside-down in the basin. Test it first; gravity feeders can keep water level stable for 10–14 days.
Q: Is distilled water mandatory?
A: Not mandatory, but using tap water will leave white mineral crust on the pump and rocks within 3 weeks. A $1 gallon of distilled water lasts 6–8 weeks and prevents the crusty “fossil” look.