Cloudy water after cleaning a filter can look alarming. Urgency depends on what is happening to the fish right now — not the appearance of the water alone.
Act now if you see:
- Fish gasping at the surface or struggling to breathe
- Loss of balance, sinking, or inability to stay upright
- Sudden, widespread behavior changes that began with the cloudiness
These signs suggest the situation may be affecting living animals directly and should not be delayed.
Wait and observe if:
- The water is cloudy but fish behavior looks unchanged
- Fish are swimming normally and interacting as usual
- No sudden distress appeared alongside the cloudiness
This does not mean the issue is resolved. It means the situation is not unfolding minute by minute.
If you are unsure which category applies, take that uncertainty seriously. When living systems are involved, doubt itself is information.