Wire Spools Tipping

I now own 3 wire spools to do trials on. If I jump and just reach the edge of one wire spool, the spool almost tips over causing me to have to jump off. This is pretty nervracking for trials. Anyone have any ideas on how to reinforce the spools to prevent tipping?
thanks

Put something heavier than you on the bottom. I’d say logs or rocks or bricks. When my pallets were tipping I put three huge tires on the other side to counterweight and that worked pretty well.

sandbags, you can usually find em for cheap at a hardware store… couple 80 lb bags per spool ought to keep it up