From StrategyWiki, the free strategy guide and walkthrough wiki

Here, you can either surf or go through Mt. Mortar, it is recommended that you surf.

Trainers			Items
	Pokemaniac Shane: 960 Nidorina (lvl. 16, 400 EXP) Nidorino (lvl. 16, 403 EXP)		Ultra Ball Pink Apricorn (Tree) Green Apricorn (Tree)
	Fisher Tully: 720 Qwilfish (lvl. 18, 385 EXP)		Yellow Apricorn (Tree) Super Potion Water Stone (Talk to Fisher Tully and get his number)
	Hiker Benjamin: 512 Diglett (lvl. 14, 243 EXP) Geodude (lvl. 14, 258 EXP) Dugtrio (lvl. 16, 523 EXP)

[edit] Pokémon found (Water)

Morning	Day	Night
Goldeen	Goldeen	Goldeen
Marill		Seaking

[edit] Pokémon found (Grass)

Morning	Day	Night
Spearow	Spearow	Zubat
Ekans	Ekans	Golbat
	Rattata	Rattata
	Raticate	Raticate
	Fearow	Marill