Run a tandum filter and rinse at regular 30 or 60 minute intervals this should help ... When I had to change out my substrate for diffrent reasons I emptied the tank used a hold bin and placed LR
and critters in it ... placed the sand and seeded from another source , scaped and used a pump and tube ran the H20 over the LR
and kept out about 3 gallons I topped off with new salt water and redrip acclimated the fish . This took about an afternoon to do , then once the fish were in added a bit more salt water lights out for the day and ran 2 filters rinsing 30-60 minutes and replacing the next day ... We were crystal clear in about 3 hours ... I also have a nano so it made it easier on me ...
We did have a bit of a diatom bloom but that is normal and did clear for me with in about a month HTH