"Yes armor level is 25 and hit points set to 400. hmmm that could be the culprit"
Stock Mark 14 120-180 hit points, Mark 16 180-350 hit points. Stock destroyer one fish removes all the hit points (100), the enhanced DD with 400 hit points would require two fish. So your options are restore the DDs to the original value, or get torpedoes with more boom.
http://www.subsim.com/radioroom/down...o=file&id=4380