How to treat unexplained fish death in an aquarium
What does it look like?
- Sudden and unexplained death of single or multiple fish
What are the fish doing?
- Fish are laying stationary on the surface of the water or the bottom of the aquarium
- Fish are not moving
What should I do?
- Test water for underlying quality issues and treat accordingly
- Check for signs of de-oxygenation / fish gasping, breathing rapidly.
- Look for obvious physical symptoms on the dead fish or the rest of the tank for better diagnosis
- Consider the age of the fish if only one has died and others appear healthy
Why does this happen and how do I prevent it?
Test your water quality. Water quality issues are often invisible to the human eye and can have dramatic effects on the wellbeing and health of your aquarium without any obvious warning. Testing regularly can allow you to address water quality issues before it is too late.
Look for obvious physical symptoms on the dead fish which can suggest the cause if death. If there are physical symptoms on the fish, consider another diagnosis for the death and treat the remaining fish accordingly.
If only one fish in your tank has died consider the age/lifespan of the fish as, like all animals, fish will just die from old age.
Some other issues that could cause unexplained fish death are:
- De-oxygenation – in this case often only the larger fish will have died because they have a higher oxygen requirement.
- Acute systemic bacterial infection – fish die before exhibiting many physical symptoms.
What treatment should I use?
Easy Test Master Test Kit
The secret of trouble free aquarium fishkeeping is ensuring your fish live in ideal water conditions. Unfortunately the key toxins and pH are invisible to the naked eye.
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