We just bought a 100g tank and are setting it up. Our local fish guy says he heavily plants his tanks (lined with premade dirt boxes, then gravel) and does not wait to add the fish. He showed us several tanks where he did this and the fish looked ok. This seems to go against everything I am reading about completing a fishless nitrogren cycle. I don't know if this works for him because the tank is large and there are lots of plants to take up ammonium. This is an attractive notion, but we don't want to do the wrong thing for our fish.