There is a PDF you can open from Carl's site that shows a list of fish that can be found at each fishing spot. It's a bit difficult to read, but it lists exactly what each spot will generate.
Both the fishing spots in Sylvan Glade have the angler, but only one has the piranha. The PDF noted above is a bit mismatched with the names on the lists for the Glade, but I believe it's the pond that has both. (The pond doesn't have a fishing sign, you just click on it to fish.) You'll know you've got the right one if you get the 'definitive' candle sculpture or a pomegranate; you've got the one with just the angler if you get a voodoo doll or 'no place like gnome' sign.
There is also a spot at the far north end of the Oasis Springs park that has both. (It's the right one if you get a guitar or pomegranate.)
According to Carl's list, the best bait for both is medium-sized fish like bass and catfish.
