There are several designs that are filled with oil and give the SHB a place to run from the bees and drown. I tried most of them and now use an oil tray under the screened bottom board. You can buy those from the suppliers too or take a trip to the grocery and buy a $2 aluminum cookie sheet. Before you let your hive die Checkmite + works for Varroa and small hive beetles. The bees will abandon the hive when it gets infested. It will leave an oily looking mess with damaged combs as you describe.