Using my sandbed from old to new tank?

[toytech]

I rinsed and saved most of my old sand from my last tank to use on my current tank as well as bleaching all my liverock and dried it because I wasn't setting up my new tank for almost 2 years . Now its set up nitrates seem to be an issue that ive never had before and im inclined to think its the sand and rock , even though I cleaned everything as much as I could I had nitrates with no fish in the tank for months and still do .