Plants Not Absorbing Nitrates?

I have a bunch of plants in my 50 gallon tank, but when I test the water (every other day) I always getting a reading between 40 and 80 ppm of Nitrate. I use an API master test kit. The other parameters are 0 Ammonia, 0 Nitrite, and 40 Nitrate.

 

Depending on your plants will depend on how much they use. Root feeders will remove very little. Floating plants remove the most since they feed off the water column.

 

Depending on your plants will depend on how much they use. Root feeders will remove very little. Floating plants remove the most since they feed off the water column.

Oh.. that explains a lot. I have amazon sword, rosette sword, aponogeton, and java ferns. I'm hoping to get some water lettuce in the spring.

 

Have you tested your tap water supply? You could have equally high amounts in there (my tap water is 40-80ppm actually and I'm trying to resolve the issue before I purchase more delicate fish)

 

Have you tested your tap water supply? You could have equally high amounts in there (my tap water is 40-80ppm actually and I'm trying to resolve the issue before I purchase more delicate fish)

My tap water is 0 ppm

 

My tap water is 0 ppm

Faster growing plants consume more. However I hope you're not relying on them. You should do an immediate water change of 50% then another 50% change tomorrow. Those nitrates can slowly lead to poisoning esp over longer periods of time