For small operations, the best way I've found to reduce sand is to let the syrup settle for a couple days in the fridge between last boil and bottling.
Carefully avoiding the sand in the bottom while pouring it into the pot to bring up to bottling temp. Then do a final filter with the felt and prefilters while pouring into your bottling container.
Filter aid does nothing for gravity filters besides clogging the filters.
2015 - 8 buckets, 332L sap, 8.5L syrup - Barrel evaporator, 2 steam pans
2016 - 8 buckets, 432L sap
2017 - 10 bags, 470L sap, 9L syrup
2018 - 20 bags, 1050L sap, 17.6L syrup
2019 - 20 bags, 970L sap, 22.2L syrup
2020 - 17 bags, 813L sap, 17L syrup