Why are my pond koi acting weird?
Our koi fish are very active. They swim all over the place. Sometimes they will spread out all over the pond and move slowly about. The moment they see us though, they are a flurry of activity in anticipation of being fed.
It is really important to be aware of how the fish are normally so you can detect abnormal behavior.
What is normal koi behavior?
Koi that are not used to people walking up will hide. They are afraid of people until they learn not to be.
When koi are fed on a regular basis they will come up to greet you when you walk up. Early in the spring they will be more shy. I know my fish are a bit this way in early spring as the feeding season begins.
Keep in mind that if the water is below 50 degrees they will be less active and may not come up to greet you. The colder the temperature, the slower fish will swim.
Fish trauma?
If your fish are normally very active and come to see you when you walk up but suddenly are hiding and acting frightened, They have likely had some trauma.
Reasons for trauma:
- The fish have been chased recently with a net.
- Pond cleanout has stressed them out.
- A predator has recently been stalking them.
What to do when the koi are acting weird
If the koi have recently had trauma and are hiding like something is after them, you may not be able to see them well and some fish may be in complete hiding. Try to walk up to the pond each day so they can see you. drop in 3 pieces of fish food and wait for them to come up. If the fish do not come up then net out the food before it gets to the skimmer and try again tomorrow.
When they do come up, then feed them what they can eat in 5 minutes. Make sure to feed them this way every day. They will be back to themselves in no time.
Once they are swimming around again normally, you can count how many fish you have and look over them to see if any of them are injured.
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How to know if it's a water quality issue
There are fish behaviors that may point to water quality. You need to address water quality quickly to keep your fish from suffering and perhaps, dying. So test the water or call us to test it!
When the fish behavior looks like they are gasping for air, guess what? They are generally actually GASPING FOR AIR.
If you were speaking with you, I would ask if the waterfall/pump is running and if you have aerators in the pond. Turn them on! That is how they get oxygen!
Another cause for gasping for air can be that there is too much copper in the water. Do you have an IonGen or Ionizer? Turn it off and do a partial water change. Now.
Has anything been added to your water that is not normal? Did your Uncle put in something like algaecide or something else? Do a partial water change right now.
Did you know chlorine can burn gills which would cause fish to have a hard time breathing? Yep. Has a large amount of water been added to your pond recently? Do a partial water change.
The BEST way to know if it is a water quality issue is to….(drum roll please…) TEST THE WATER! Yes! Use a water test and see if the strange behavior is due to high pH or an ammonia spike. Do the water test BEFORE you do a water change. Anytime my fish act weird I do a water test and if anything is off, I do a partial water change and I use a dechlorinator.
Kristi’s Tips
Adding water: Remember to use a dechlorinator if you are adding more than 20% of the total water volume.
Fish addition: if you have added too many fish at once, you can cause an ammonia spike which can kill all the fish. Add a few at a time. Wondering how many fish you can have in your pond? Click HERE.
Fish over crowding: Too many fish can cause ammonia spikes if the filtration and plant life is not enough to process it, causing an…(guess what I am going to say…) an AMMONIA SPIKE!
Illness or parasites: Weird fish behavior can be a sign of if illness or parasites. Test the water. If they water parameters are all good, do a partial water change and watch the fish carefully for odd behavior. Contact a local fish vet and describe to them what you have done and how the fish are acting. They may know what the issue is and how to treat it.
If you just moved to a house with a pond and need lots more info click HERE.
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