Sounds good on the filter media stacking though I usually put the bio-media in last as it helps catch any finer particles. I wouldn't bother changing it until the next time you open the filter.
Be a bit careful on how much total media you put in the filter because you don't want to force the top lid on the filter and compress the media too much. There is also the chance you can break the legs of the lattice screen if you need to 'push' the media down to get the lid on.
Also, there is no need to crank the latches down. I just do mine finger snug, alternating latch tightening as you do when putting lug nuts on your car tires. Did you double check that the o-ring in is the groove on the lid? It usually comes loose in the bottom of the filter canister.
Be a bit careful on how much total media you put in the filter because you don't want to force the top lid on the filter and compress the media too much. There is also the chance you can break the legs of the lattice screen if you need to 'push' the media down to get the lid on.
Also, there is no need to crank the latches down. I just do mine finger snug, alternating latch tightening as you do when putting lug nuts on your car tires. Did you double check that the o-ring in is the groove on the lid? It usually comes loose in the bottom of the filter canister.