HELP! Fish Breathing Heavy

[Hamsnacks]

Last night at around 9pm I did a 30-35% Water Change, and a vacuum. Nothing out of the ordinary.
The only thing that may have been different is, I would of added more Prime than Usual because our Tap water has been really bad. Also added a few scoops of Seachem Equilibrium.
Today at 1:40pm when the lights came on, I noticed every single fish was breathing heavy. One other change would of been the CO2 would have been on for an extra half hour than usual, didn't remember to reduce that by half hour.

No fish is going to the surface, but every single one is breathing quickly, from the plecos and corys to the tetras and Angelfish. But still swimming around.

Parameters:

125 Gallon Long

Temp: 78-79 Degrees
Ph: 7.6
Ammonia: 0
Nitrite: 0
Nitrate: 40-80ppm

This is the first time I have had any issues like this and of course on Christmas when the family is coming.

I have turned off the CO2, put in a large Air Bubbler with 4 hoses and just waiting now. Should I do another water change? Do I just wait?

Any advice would be helpful!

Thank you

 

[Colin_T]

You poisoned the fish with CO2.

During the day when there is light the plants will use CO2. When it is dark plants use oxygen (O2) and release CO2. If there is nothing using the CO2 at night, there is no reason to add it. So turn off the carbon dioxide at night because the plants don't use it when there is no light.

Increase aeration and do a water change and leave the CO2 off for at least a week so the fish can recover.

 

[NickAu]

Last night at around 9pm I did a 30-35% Water Change,
Nitrate: 40-80ppm

Has your tap water got high nitrates?

Unless there are nitrates in the tap water you are not doing big enough water changes.

 

[Hamsnacks]

No sorry if I wasn't clear, the CO2 comes on an hour before the Lights and turns off an hour before. But I reduced the Lights to 7 hrs starting today so the CO2 would of been on an HR and half before the Lights.

Been doing smaller water changes due to the high ammonia in our tap water lately.

I ended up doing a 50 percent water change and everyone in the tank now looks like they are back to normal.

I won't be using Equilibrium anymore, that's the only thing that has changed. Don't know what affect that would have but that's the only factor I could think of.

 

[Hamsnacks]

Just checked up on the fish they are now breathing heavy again, have no idea why. During the day after I did the water change they were back to normal.

I will put the bubbler back on and keep it there for 48hrs. Had to turn it off due to the guests was just too loud. But never had any co2 issues prior to today, doesn't make sense.

 

[Hamsnacks]

@Colin_T @NickAu

The night before I was doing heavy vacuuming and actually flipping over the Sand, it was getting a bit brownish so I wanted cleaner looking sand on top. Could I have been releasing gases that were trapped in between the Sand?

 

[NickAu]

May be, This is why Malaysian Trumpet snails are essential they burrow through the substrate turning it over and releasing any gasses in the substrate.

 

[SaltNoob]

How are the fish doing now? If it is the substrate that caused this, it is common that a lot of detritus buildup happens and when you stir the ammonia level increased rapidly.

 

[Colin_T]

If there is gas in the substrate, you will see the big bubbles float up when you disturb the gravel. And if it is hydrogen sulphide gas you will smell it.

If you didn't see any bubbles, then it was unlikely to be gas in the substrate.

You don't normally get anaerobic gasses in the substrate unless it is more than 4 inches thick and has lots of rotting organic matter in it.