Complex sentence: The Mark 45 was absolutely massive compared to the torpedoes prior to it; known as an anti-submarine torpedo, it weighed 2330 lbs compared to its predecessors' average of around 450 lbs. Also, all previous torpedoes were non-nuclear and therefore had much less of a payload.
Split into simpler sentences: The Mark 45 was absolutely massive compared to the torpedoes prior to it. It came in at a whopping 2330 lbs. While it's predecessors averaged around 450 lbs. But as I had mentioned, all previous torpedoes were non-nuclear and therefore had much less of a payload.