Need help fish breathing heavy

Madmansreef

New Member
View Badges
Joined
Apr 12, 2026
Messages
6
Reaction score
1
Location
Tampa
Rating - 0%
0   0   0
Good evening,
Earlier this evening, I thought I had set my return pump to feed mode, but I was mistaken. When I came back, my flagfin angelfish was acting erratically. I turned the lights on and found all of my fish gasping for air, which I don’t understand. I have a Nero 7 and an Orbit 4 running, so I assumed there would be sufficient water circulation.

At the moment, I have four large airstones running at full blast in the tank.

I’m not sure what caused this issue. It’s possible there was an algae bloom during the 3–4 hours the return pump was off, but I also noticed three uneaten pieces of clam in the tank.

For reference, my system is a Waterbox 220 FOWLR tank with several angelfish, triggerfish, and three eels.

Any help or insight would be greatly appreciated.

20260412_012909.jpg
 
Last edited:

Mebbid

Active Member
View Badges
Joined
Jun 3, 2017
Messages
444
Reaction score
400
Location
Jackson, MI
Rating - 0%
0   0   0
imho in 3-4 hours the only reasonable explanation is lack of oxygen from decreased surface agitation. Neither algae blooms nor decaying food would happen fast enough to go from normal and healthy to fish gasping for air in 4 hours. The decreased surface agitation in combination with the photosynthetic organisms in your tank consuming oxygen and gassing off co2 with the lights off could have been the contributing factors to make that happen.
 
OP
OP
M

Madmansreef

New Member
View Badges
Joined
Apr 12, 2026
Messages
6
Reaction score
1
Location
Tampa
Rating - 0%
0   0   0
thank you so far the only one that looks ill is my flag fin angel but I havent seen my Banana wrasse or my clown trigger which has me worried, is there any solution to this do I need to do a water change
 

Mebbid

Active Member
View Badges
Joined
Jun 3, 2017
Messages
444
Reaction score
400
Location
Jackson, MI
Rating - 0%
0   0   0
thank you so far the only one that looks ill is my flag fin angel but I havent seen my Banana wrasse or my clown trigger which has me worried, is there any solution to this do I need to do a water change

What return pump do you use? How does the feed mode on it work?

My pump controller itself has a feed mode on it that I use instead of ever turning it off or on except for water changes. If I didn't have that I use a Kasa wifi smart strip that you can set to turn the outlet off for a short period of time and automatically turn back on.
 

Euphyllia97

FOWLR and reef member
View Badges
Joined
Oct 22, 2019
Messages
1,026
Reaction score
1,493
Location
Belgium
Rating - 0%
0   0   0
In that amount of time it is most probably lack of oxygen. The powerheads might have been still working, but they do look to be in a position where only those are not creating enough surface agitation. You did the right thing by adding the airstones. WC will likely do more harm than good now. Your fish might be hiding due to the stress or might have suffocated. Time will tell, but don’t panic just yet… When you are speaking about “looking sick” what do you mean by that? Only heavy breathing? Did this improve a bit already?
 
OP
OP
M

Madmansreef

New Member
View Badges
Joined
Apr 12, 2026
Messages
6
Reaction score
1
Location
Tampa
Rating - 0%
0   0   0
What return pump do you use? How does the feed mode on it work?

My pump controller itself has a feed mode on it that I use instead of ever turning it off or on except for water changes. If I didn't have that I use a Kasa wifi smart strip that you can set to turn the outlet off for a short period of time and automatically turn back on.
a reef octopus not sure the model number will let you know in the am, am I doing a over kill with these 4 bubblers? can this much air harm my tank?
 
OP
OP
M

Madmansreef

New Member
View Badges
Joined
Apr 12, 2026
Messages
6
Reaction score
1
Location
Tampa
Rating - 0%
0   0   0
In that amount of time it is most probably lack of oxygen. The powerheads might have been still working, but they do look to be in a position where only those are not creating enough surface agitation. You did the right thing by adding the airstones. WC will likely do more harm than good now. Your fish might be hiding due to the stress or might have suffocated. Time will tell, but don’t panic just yet… When you are speaking about “looking sick” what do you mean by that? Only heavy breathing? Did this improve a bit already?
the flag fin was laying flat breathing rapidly but ever since I added the airstone he moved away and I havent seem him again, in regards to the powerheads I just moved the nero 7 due to it kicking up my sand
 

Mebbid

Active Member
View Badges
Joined
Jun 3, 2017
Messages
444
Reaction score
400
Location
Jackson, MI
Rating - 0%
0   0   0
a reef octopus not sure the model number will let you know in the am, am I doing a over kill with these 4 bubblers? can this much air harm my tank?
nah, the air bubblers are fine. Just gotta be careful which button you are hitting on the controller for the varios pumps, make sure you're seeing the light indicating how long of a pause when you do pause it.
 

TOP 10 Trending Threads

WHAT AMOUNT OF LIVE ROCK AND SAND SHOULD BE PRIORITIZED FOR OPTIMAL BIODIVERSITY/FILTRATION?

  • 100% live rock + bagged sand

    Votes: 34 28.1%
  • 100% dry rock + 100% live sand

    Votes: 41 33.9%
  • 50/50 live/dry rock, 50/50 live/bagged sand

    Votes: 27 22.3%
  • 75% live rock, 25% live sand

    Votes: 11 9.1%
  • 25% live rock, 75% live sand

    Votes: 8 6.6%
Back
Top