- So the mermen live separately and in secret than mermaids? Then how do any of them mate? How is it that new merpeople are born if the two haven't been in contact in centuries? One could argue that the mermen are most likely mating with human females but that wouldn't work in reverse with mermaids given how they avoid humans at all cost. There have been a few times when the mermaids have mentioned having parents, so perhaps they are not asexual.
- Maybe they create offspring via magic? Given the range of powers we've seen, it is possible.
- Well, they do call young mermaids hatchlings, this could be that they lay eggs in this universe.
- Once the trident is returned to the chamber near the end of S1, why don't the mermaids seal it up in some way? Like, fill the cave passage that leads to the antechamber with rock, and seal the rock in place with concrete? Oh, it could be re-opened eventually with enough effort, but this would hugely slow down anyone who made the attempt.
- The pod's elders are stupid. In Season 1, the presence of just one landboy-turned-merman - oh, they eventually learn he was born a merman, but they don't know that early on - causes the entire pod to flee Mako Island and environs because "mermen are dangerous." But the elders must have known what we learned later from Rita, that there was a war and a very large number of mermaids were able to defeat the mermen, even though the mermen had the trident. In the beginning Zack is very inexperienced, his powers are weak, and he doesn't have the trident. But instead of decisively sending a dozen or so of their best, whom you'd think could have dealt with Zac easily, the pod's elders send three young and inexperienced mermaids who haven't even completed their training yet back to Mako Island to fix the problem. It's really a good thing they stumbled onto Rita; without the information she gave them things could have turned out far worse.
- It's stupider than that; the pod didn't send the main trio to fix the problem. They banished the girls and told them they were on their own, without any mention of fixing the problem. The trio decided to do something about Zac on their own initiative because they figured that was their ticket back into the pod. In essence, the pod decided to leave and ignore the problem entirely.
Headscratchers / Mako Mermaids: An H2O Adventure