I have pool sand in my tank. I've never stirred the sand and I've had no problems. It's about 1.5 inches deep with plenty of mts. I also have lots of plants, and the roots are good at breaking up gas as well. Since my daughter was born a few months ago, I sometimes have to go a few weeks without any water changes, so it's a very forgiving substrate.
rules of thumb:
not too deep, 1.5 inches doesn't sound deep, but it is when you get it in there.
MTS and rooted plants are great insurance.
lightly stirring the substrate is great if your decor/plants allow.
Some fish like to burrow some, so if you have that type it can also help
sand is an awesome substrate, and I've really liked the pool filter sand. It's cheap, attractive and is heavy enough that it isn't moved around by currents.