Ace Of Spades
Fish Gatherer
If the OP says the fish are fine and you can see no positive proof they are fighting/have injuries then you're all jumping to conclusions. There are exceptions to every "rule" in fish keeping. Do you know this person does not keep these two bettas in 180g tank, no?
The fish could easily rest on the floating wood for breathing, as they seem to be doing, not struggling to reach the surface, you can't see the rest of the tank, don't immediately think there are no other places for them to rest i.e. plants.
They look stressed? He's just turned on the lights, often fish will be washed out when the lights are first turned on, they've been in near darkness normally and aren't fully coloured up.
Piranha can also be kept with small fish. So maybe I would try them with a guppy, it wouldn't see it as worth the effort to chase and kill to eat.
Yet more idiots on the forum jumping to conclusions and telling people they are wrong again without fully knowing the circumstances.....
So True