I'm about to change the sand in my filter (Hayward S210T Pro Series 21"). First time I've ever done it. The old sand is out now, so there's no going back.
The owners manual, and other guides I have read, stress the importance of covering the 'under-drain' stand-pipe and keeping the entire lateral assembly centered and firmly on the filter vessel base when adding the sand. An accessory 'sand shield' (SX202S) is provided with new filters to assist this.
From older manuals, it looks like the shield was originally in the form of a dish that fitted into neck of the filter vessel, with slots to let the sand through and a central cap to cover and center the stand-pipe. Don't what it was made of. I assume plastic.
With newer models, this appears to have been replaced by a fold-out piece of corrugated cardboard. From the illustrations, the original type does look more secure to me.
My filter is second hand and unfortunately the previous owner did not retain the 'sand shield' or can recall what type it was.
I did inquire at a local pool store. They said, just put some tape over stand-pipe (to keep sand out) and, if your not experienced at it (yeah, right), have one person hold the stand-pipe in place while another adds the sand.
I need to do this tomorrow and with no-one to assist. Does anyone have any tips, tricks or DIY alternatives for keeping the stand-pipe/lateral assembly in place? I'd hate to have to start all over again because it shifted or lifted up.
PS - I know it's best to partially fill with water before adding the sand so as to avoid damaging the laterals.