Thats what I believe and have been saying that for decades and is my main method.
Manda0597, to put that into perspective, I add mud to my tank from the sea. I used to add garden soil and my fish have never been sick or quarantined and the tank is almost fifty years old.
I believe it is the bacteria in the "dirt" that is part of that reason for health and the other part is to add some live food like worms because of the bacteria in their gut.
But for now, just help the bacteria get stabilized and that takes time no matter what you do, but additives can make that time longer.
Good luck