So i have a 130gal in my house that i got a few months ago. Upon getting it home i put the sand and rock in it and filled it up with water.at the time i didnt have cash left for salt so i put a few powerheads in to move the water. I just purchased salt today and have not added it yet. My question is since my tank has been full for two months now( no salt) has the nitrogen cycle taken its course? If so will adding salt affect it?