Hi Brooke and Welcome! Yes, bio spira is an instant cycle. Some folks do show traces of ammonia and nitrites for a few days after adding it to the tank, but it should be minimal. I have used it 3 times and have had complete success. The neon tetras are very beautiful but unfortunately very sensitive, and until recently are probably mostly wild caught. Everybody I know (including me) have not had good luck in keeping them alive for very long, so keep that in mind if you decide on getting them. Otos are good, but they are like the neons and are very sensitive and die for no apparent reason. You would also not add them to your tank until you had a good food source for them. They prefer the brown algae you usually see in newly established tanks called diatoms, but they will eat green algae. The diatoms will disappear as your water ages. Something a little more hardy for your tank would be about 3 cory cats to keep the bottom of your tank clean. Or you may want to consider getting a pretty betta as your show fish and upping the cory cats to 5 or 6. I think a few ghost shrimp added in the tank would also be awesome with this combo. Your kids will love them!
You can learn more about cory catfish at
Planet Catfish