Yep, usually you will get an Array of DataRows when you perform some type of Filter calculation to pull in specific rows. This is a good thing, because then you can only loop over certain rows of a particular data set.
Simply use the regular ForEach activity rather than the For each row. Then, set the ArgumentType to DataRow, since the array contains a set of DataRows.
I don’t recommend converting the set to a DataTable (which can be done by using .CopyToDataTable next to your Array), because then you need to check the .Count of the Array prior to conversion or you will get errors. Additionally, you lose the original data set, when you do that, so you can’t update the entire table throughout the process.
I hope this helps.