From Bulbapedia, the community-driven Pokémon encyclopedia.
The Remeyo weed underwater in the anime
Remeyo weed (Japanese: シレット水草 Shlet water herb) is a type of herb that grows on lake bottoms; some Water-type Pokémon are specially trained just to be able to retrieve it. Ash used it to cure his, Iris's, and Cilan's Pokémon after they were poisoned by a group of wild Foongus in Facing Fear with Eyes Wide Open!.
- Remeyo weed is similar in both name and use to the Salveyo weed that was used to cure those inflicted with a status ailment.