please help fish sitter over fead my tank

[boots]

so to make a long story short ,i come back from my vacation thinking that I would probably be a little off in my water perameters. So the first thing i do is a water sample and all seems well untill I get to the nitrats and they are out of this world. So i did a healthy water change and one more three days later and they have not come down very much. is there anything that i should be doing or could be doing


thank you in addvance

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