My Arowana is gasping after water change

[Dhiviya]

I’m worried on my arowana as it’s gasping and keeping opens its mouth after water change. It was a normal water change done as usual.
why do my aro is gasping?

 

[tlindsey]

I’m worried on my arowana as it’s gasping and keeping opens its mouth after water change. It was a normal water change done as usual.
why do my aro is gasping?

How often do you do water changes? Are you consistent with the water changes? During water changes are the temperatures about the same? Also are you using a dechlorinator?

 

[duanes]

How often do you do water changes? Are you consistent with the water changes? During water changes are the temperatures about the same? Also are you using a dechlorinator?

Good points
Also (and this may have to do with how often you do water changes, and volume of water in a water change).
What is the pH of your tap water?
And what is the pH of the water in your tank, just before a water change?