Fish suddenly dying

[Micky1]

I have a pond about 3000 gallons and have had fish for 20 plus years,however suddenly this week I have lost four fish, I have done the ph,nitrite,nitrate,ammonia test and these are ok. I have noticed a strange smell from the pond today but it’s not there long. I have about 8 koi,1goldfish,1orf there maybe more but I can’t see them due to the condition the pond has developed into. I have a good filter and uv and also have air going in as well, any ideas ?

 

[TheFishGuy]

OK does not tell us much, some people will say a nitrate of 80 is OK, while it really isnt, take a picture of your values, or list the nmbers here, you say that "the Condition the pond has developed into" what does this mean, you may need to clean out leaves, and have you intodurced any fish recently, we need more infor, and as always pictures to help us understand your problem

 

[j.w]

@Micky1
I'm wondering if you might have too many fish for your pond and the water is low in oxygen for all of them? Koi need about 1000 gals per fish especially if they are large koi.

 

[Mmathis]

Hello and welcome! I’m thinking along the same lines as @j.w . As your fish grow larger each year, they are producing more waste products, so what was a balanced pond 2 years ago, can be thrown out of balance by a small change. And as @TheFishGuy said, telling us the actual number values for your tests would be helpful.

 

[addy1]

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