ok, no problem.
Remember, in the reef, the fish and coral are used to waves crashing all the time. When these waves crash, they kick up sand; thus, your inhabitants won't be negatively affected by your adding sand and making the water cloudy. You will be more bothered by it than they will. Eventually, the water will clear. If you want to filter out the finer particles, you can use a fliter sock or canister filter, although it is not necessary to do so; the finer particles can be quite beneficial.