depends on size you get the tig. def not a beginer fish. If you are getting it small (under 10") keep it in something like a 55 to 75 with not threatening tank mates. get it eating worms, guppies, or frozen foods, BUT DO NOT OVERFEED, they are very sensitive to that. provide excelent water flow and airation, tigs come from an area of the amazon that is essentially white water rapids. Keep low lighting as they are nocturnal, and provide hiding places.
Bigger ones (over 10") will need a 180 gallon+ and are much hardier and are pretty much like any other big catfish (although tigs max out at around 3', smaller than most "giant" cats.)
hope that helped.