Hello! I was told by the guy at Petco that all Tetras, including the Red Eye Tetras that we have, should be kept in odd number groups only but everywhere I look on the net it says 6 or more???? I don't trust the Petco guys father than I can throw them due to all of the bad advice we have gotten in the past month!But we know that 3 Tetras is not enough - I think they would be happier and more secure with a larger group, like 6!Does anyone here have an opinion or experience with this odd numbers thing?Right now we only have the 3 because we are cycling and the ammonia is still an issue..doing water changes and I think we are on the decline of this spike now thankfully!We will had more Tetras when the tank is good to go.Also, does anyone have feelings an when an air pump is needed? I had a tank a loooong time ago and I had a pump, but it was really more for the bubbles from the air stone (which I liked) rather than anything else.I have a 10 gallon tank with a Whisper filter. Thanks! Jenni