Just be careful you don't want to start trying to cycle a tank with a bunch of sand and a inch of water that has been in stagnate for 2 weeks. Doesn't sound like a healthy start.
Just rinse the sand in the tank and do a quick drain of the water after you fill like 20% up, ya know just to get the old water out and have a good rinse.
well if i fill it and have the filter running then start fishless cycling it and do some water changes with a gravel van. You think that will fix everything?
It wont take you that long, just rinse the sand out inside the tank if you want to save time. You can have one hose draining water from one end of the tank. While you fill and push the hose through the sand on the other end of the tank. And just cover the bottom of the tank get it nice and mixed up, and rinsed out.
If its not possible to do both filling and draining at the same time, then just take it step by step.
But I would do this now before you start to add your filters. Should not take that long, better to do it now give you a peace of mind, and a healthy start to your cycling of your tank.