a 6ft x 2ft is ok to house for about 18mths i would say depending on speed of growth. i have seen tigs pushing over 2ft so probably at some stage you would need a wider tank. mine continues to grow extremely fast. got him at 9inch and now 17inch after about 6months. a grow out is prob a good idea if you get a small one. tbh i got mine feeding pretty quick using a tweezers and frozen prawn and smelt. gently rub the food on the whiskers and they will grab. aternatively feed at night as they are nocturnal and very active then. anyways thats my experience and i do not claim to be an expert.. thanks