At level 25, I know a great spot for you to farm, and you will get a little EXP while you are there.
You know the pond in the middle of La Thene Plateau? Head there and look for a cliff that will lead down the cavern north of the pond in La Theine.
Find the path down, then head to the end of the cavern, where you will find a cave. The Poisonous Fungars do agro, so you may need to figt your way through.
There are 3 caverns and 2 tunnels, when you make it through the 2nd tunnel, you will be in the 3rd cavern. You will know you are here when you see the Stone Monument used in the Selbina Clay quest for the Crawlers nest Map.
Now that you are here, start killing Fungars, Huge Wasps and Bats in the cave. You will be collecting Beehive Chips, Giant Stingers, Sleepshrooms, Bat Wings, Bat Fangs, and Dark Crystals. All of which sell very fast, and for a hefty amount of gil per sack.
But who wants to just farm for hours? The best thing about this spot is a NM that spawns there about once every 3 hours. The Tumbling Truffle drops a Fungus Hat. It sells for about 15K, somewhat small game, so it is rarely camped.
Empty out your inventory, and get to work. On a good day I'd pull 25K an hour, and if I got the NM and the drop, that jacks up the yield to 40K an hour! Not bad at all for a level 25 player.