My personal recipe:
最難就是timing, I always use this guideline
every 1lb, 15 min. @ medium high stove setting, 水滾開始計, 水滾才放魚
but 蒸 should use fresh fish otherwise it will be "sang". 冰龍利柳 is an exception, not sure why it is not "sang", people said the chemicals they use to preserve it makes it not "sang"