Super Rod: Route 9 (70%), Melemele Sea (25%), Hau'oli City (25%, Only in Ultra Sun & Ultra Moon)
SOS Encounter: Route 9, Melemele Sea
Surf: Melemele Sea (40%), Hau'oli City (15%, Only in Ultra Sun & Ultra Moon)
Its base catch rate is 225 out of 255 (higher is easier); the catch rate calculator works out your odds with each ball. For the look, the best colour match is Love Ball or Heal Ball.
Luvdisc in every game · Pokémon Sun, Moon, Ultra Sun & Ultra Moon interactive map (Alola)