Hey guys, so I've been struggling to get my form down on deadlifts, my hips always shoot up and my back rounds. Even with lighter weights my form isn't that great and it gets progressively worse as i go heavier. Right now my set up is: big chest, sitting back on my heels with my butt pushed back, squeeze my lats, get my glutes/hams fired up, pull the slack, and explode while pushing my feet through the floor. I mainly workout at an LA Fitness and the bars there are terrible for deadlifting, there's hardly any whip. My form is a lot better when I use an actual deadlifting bar but unfortunately that doesn't happen very often. Whenever I do reverse band deads with a band that's 420 at the bottom and 545 at the top my form is pretty good but I can never get it to cross over to conventional deads.

Here's a video of a few sets of 405, 455, then 470.
https://www.youtube.com/watch?v=Ey4pkHUIAtU

Any tips/constructive criticism would be greatly appreciated!!