Gasping for air?

I'm very confused are my fish or more specifically my rosy fined tetra gasping for air. I have a 72l it has a diy sump working nicely and a corner filter runing constantly in the tank for extra filtration and for emergency power outs as there are many and they last long. I was just sitting watching my 2 rosy fined tetras male and female they look like they are courting been doing that for 2 months now and then the one shot to the top of the tank from the bottom came back down blew a bubble and then carried on "courting" it shot up the same way the corys do is this gasping for air or is this normal I thought I had more than enough oxygen in the tank as it looks like all the fish are acting normally not staying at the top. So is this gasping for air or normal behavoiur? Thanks

 

Hi, some of my schooling fish do the same thing. The rest just swim around like nothings wrong. Noticed it three months back
and none of them died since then so I guesse its normal.

 

That's good to hear I had a neon do it a few weeks ago and got really worried. Should have asked then thanks

 

ya saw that with a big gold fish at the pet shop he said that fish do that wen they are hungry

 

lol,i think it's normal but if you think there is to little oxygen in the tank then you can always buy an air pump.