I would have used JavaScript/JQuery:
1. Declare pageIndex(your list's current page) and pageSize(number of records to show).
2. Get the list of records in JSON format(based on pageIndex and pageSize).
3. Find the difference between the number of records returned and pageSize.
4. From the array of returned objects create another object till you reach the difference and append this object to your original array.
5. Bind your grid or whatever control with this array of objects.
6. Use window.setTimeinterval function to fetch the records and populate the grid repeatedly.
I would also like to suggest using
jqGrid[
^] It is extremely useful considering your scenario.
Hope this helps.