I've got white sand I got from destin, and it's easy to keep. The poop falls on to the top, and if you have a turkey baster, you just suck it up daily. Once a week during water changes, turn off your filter and run your hands through it to move it around, and stirr up the mulm before sucking out the water. It looks nice, though I'm switching to Fluorite for a planted tank (I'm going to keep the sand to use to cap a NPT I might do one day with a darker colored betta)
Bettas are really precise in getting food from the ground, he won't choke on the sand, I promise. If he ever does eat sand, he'll spit it out.