Peacock bass at bottom of tank gasping

[King kelberi0996]

Have you tested your water?

Yes

If yes, what is your ammonia?

0

If yes, what is your nitrite?

.5

If yes, what is your nitrate?

0

If I did not test my water...

1. ...I recognize that I will likely be asked to do a test, and that water tests are critical for solving freshwater health problems.

Do you do water changes?

Yes

What percentage of water do you change?

31-40%

How frequently do you change your water?

Every two weeks

If I do not change my water...

1. ...I recognize that I will likely be recommended to do a water change, and water changes are critical for preventing future freshwater health problems.

Hello I was shocked this afternoon after doing about 30% water change in my 120 gallon. All my fish; 4 peacock bass, a red tail, and a angelfish are now all gasping at the bottom of the tank. Does anyone know why this is happening. ph seemed a little high added some ph lower for the tank, did not seem to help. Does anyone have a solution

 

[esoxlucius]

You've got nitrite, which you shouldn't have. Your nitrate is zero which is puzzling, because after a small 30% water change, which you report are only fortnightly, i'd have thought you'd still have a positive nitrate reading. Your ph is out of whack and your attempt to suddenly correct it could cause issues. There's also a possible dechlorinator issue, did you use it? How long as your tank been up and running for?

As you can see there are a lot of potential causes for your fishes problems.