Are Bettas Amonia Sensitive?

not sure, although I would hazard a guess that a betta would be able to stand more than a neon. however, ammonia is toxic if it reaches more than0.25-0.50ppm, so any fish will get ill if your ammonia is higher than that.
 
if you're trying to decide who to cycle a tank with i'd suggest reading the sticky on fishless cycling or the different ways to seed a bio filter, niether fish are a good choice for cycling.
 
No, I found amonia in my tank and the betta died but the tetras and everything else are ok. I was just wondering because my tetras all died when the tank cycled, since then I've bought new tetras and they seem fine in the peak of this amonia spike. They've proven to be stronger than the betta at least
 
All fish have gills that can be damaged by even small amounts of amonia. Some of us are hardy enough that we could live if we lost half our lung power, but that doesn't make loseing it unnessasarily alright.

Weakened fish are more likely to get sick which is what we try to avoid haveing happen. You can't know if the betta had already impaired gills when you got him and thus had less keeping him alive than the tetras did.
 
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