The temp is to high, go down in the wattage. Too much heat will kill them. I bet 60 watts will be enough, since the bulb is so close. You also need to know that ducks sleep in between and you wont see movement. There is no way of seeing a heart beat. You may be able to hear it with a stethoscope, but that takes a little bit of practice. Also don't candle to often or open up the incubator. The drop in humidity will hurt them. Best not to do much at all, but keep the rags wet and and temp right. Do not let the rags dry out! Make sure they stay wet at night. You can have them hang over the edge of the bucket into a pan full of water, that way they will stay wet for sure. This will be a high risk hatch, so you must try to get it as perfect as possible. Low humidity will shrink wrap them, which is deadly to the duckling. Do the air sacks still look white with the light? This means they have not internally pipped. Once they pip internally they need to pierce the shell 24 hours later. From there they should hatch within 48 hours. Have a pencil ready and write down times as these thing happen (mark the eggs 1-3). That will help you to determine when you have to step in and help. It is best not to help, but you may have to.