I just finished changing the sand in the pool filter. It's a Triton, and thankfully I didn't have to cut or remove any of the pool piping. Just unscrew the top and swing the baffle out of the way.
The rest of the procedure is pretty straignt-forward. Remove the sand with a coffee can and a shop vac, then fill with clean sand. 300 pounds of clean pool filter sand. It's a dirty job, but not particularly difficult. Follow label instructions, your mileage might vary. But it's done for another four years.