# Does very high NO3 kill fish?



## JerseyScape (Nov 18, 2005)

I am just wondering if high NO3 would eventually kill fish? I was thinking about it while dosing my KNO3 today. 

Thanks


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## SnyperP (Dec 10, 2004)

Dependant on the fish really. I hate to say it, but some of my relatives never do water changes. It takes months of nitrate accumlation to kill a fish. Ammonia on the other hand can kill quite quickly in much lower concentrations.


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## Edward (May 25, 2004)

Does smoking kill people? No, not right away. However, long term exposure to higher levels has a detrimental effect. Same with NO3. NO3 is a pollutant to fish and should be maintained carefully. This is why we should use premixed solutions instead of dry chemicals. 

Edward


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## Bert H (Mar 2, 2004)

What do you mean by high? I remember reading a post sometime ago by Tom Barr where he cranked his nitrates up to ridiculous levels to see what happened. As I recall, the only casualties were some shrimp. But I am sure that prolonged effects would be harmful. I have had mine up to around 60ppm unknowingly for a couple of weeks, and didn't suffer any losses.


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## Buckeye_Robert (Mar 12, 2005)

I tested a friends tank who brags how he never does water changes maybe once a year!
It was over 100 or higher very dark red maybe 150, it's a chiclid tank

we now have since lowered it over a 2 month time frame to about 40 and still tying to lower some more.
shooting for less than 10


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