Good weight, but your back rounded like crazy. Your hips are definitely too low. You need to get on TOP of the bar and own it -- your shoulders should not be behind the bar like they are. It's a deadlift -- not a squat. You are basically trying to do a squat with the bar in front of you. Notice that your hips go up about 6" before the bar actually moves. All that movement is wasted energy. Notice the position of your body when the bar starts to move and THAT'S the position you should be starting in... without the rounded back.
Don't worry about keeping your torso upright, which is what you seem to want to do, and that is what's making you pull it rather that just "stand-up" with the weight. Get the bar closer to your shins, leave your butt in the air, and sit back until your back is flat (not upright -- just flat) and your shins touch the bar. Then fire your glutes (through your heels) and stand up. Great strength, just work on that form a bit.
Be careful with that belt -- injuries that occur with a belt on are worse than those without.