Green tiger barb swimming vertical

Hello,
One of my 5 recently purchased Green tiger barbs had developed a swimming bladder issue.
I did a water check and will attach an image.
At after I placed them in this tank, i fed them once. A few minutes later one of them became disoriented, swimming upside down and sideways. I took him out and into the quarantine tank, at that point he started floating on the surface.
I applied Epsom salt treatment since I think he's bloated (not dropsy no scales poking). After an hour in the Epsom salt (that had been covered so no light come in) I removed the cover and it swam away from the surface returning upright/vertical. Prior to the salt bath he had been swimming upside down and sideways however now it's only vertical. So good improvement!

Now he's swimming vertically like he's constantly swimming towards the bottom.
Any help please??

P. S he is not in salt bath anymore and back in the tank

 

What are the ammonia readings?

 

What are the ammonia readings?

No ammonia reading sorry 6 in 1 test strip does not include that for some reason.
Ive had a water change today though

 

Did you just fed them flakes ?

 

Did you just fed them flakes ?

Yes! And I did not pre soak it. I wanted to de stress them a little so i dropped in some flake food. Was that a mistake?

 

Then the issue probably is that they ingested to much air while eating. Take care the flakes sink the next time.
You might try sone.blanched lettuce now and the for these guys..

 

Then the issue probably is that the ingested to much air while eating. Take care the flakes sink the next time.
You might try sone.blanched lettuce now and the for these guys..

Thank you so much I just fed them Blanched peas and they ate it up like candy.
Is that all I can do for now? I'm planning on doing another salt bath if he's still in the same condition tomorrow

 

I think it will solve itself.