The next step

[Kabong]

I dont think there's any easy way to swap out for sand, But its defintlay better to do it now rather then later.
The two ways that ive heard off are

1. Bomber bags:
Turn off your power heads,
pre wet some sand, place it in a sandwich bag place,
open the bag at the bottom of your tank and slowly pull the bag up until all the sand come's out.

2. Sand syphon. (works best when doing water change)
Take a gallon of water out off the tank into a bucket.
Add sand to the bucket and let it settle over nite.
Syphon the sand into the bottom of your tank.

Both ways are going to be messy and should be done in stages.
Most reef life can handle sand getting kicked around anyway. It happens every time there a storm.