LONDON, Oct 17 (Reuters) - Aluminium prices were pounded in September by growing concerns for global demand prospects and, while the market has steadied above those lows, some analysts expect it to fall back to levels where producers will start to curb output. "I think metals prices generally will move up in the next week or so, but after that they'll fall again," said Fastmarkets analyst Will Adams, unconvinced that efforts to deal with the euro zone debt crisis will succeed. Were alu