Here's how reproduction works:
* The colony releases gametes (sperm and eggs) into the water.
* Fertilization occurs, forming a larva.
* The larva eventually settles on the seafloor and develops into a polyp called a "primary polyp".
* This polyp then produces more polyps through asexual budding, creating a new colony.
So, while it's not about offspring in the same way as a single animal, each Portuguese man o' war colony can contribute to the creation of many new colonies through the cycle of sexual and asexual reproduction.