Welcome !! I recommend no sand actually
I currently have a 20g nano, check the link under my signature to see pics and specs. I only have enough sand to coat the bottom of the glass, and I only have it there for aesthetics. I just like how sand looks.
I'll tell you my experience and you can tell us a bit more about your tank and what you are planning. What size? What were you planning to keep?
Honestly this has been a huge debate for years, but in my experience, I've always found less sand to be better for a number of reasons.
First off, the more sand you have the more chance you have of detritus and nitrate buildup. This is a BIG one for nano tanks. Our bio-levels are VERY sensitive as it is. I run carbon, have a skimmer made for 75g+ tanks, and waterchange every week just to keep things right. Second, it's harder to regulate proper waterflow to all areas of the tank with heavy sand blowing around. Third, it's tough to keep clean, if only for visual purposes. Fourth, Astrea snails fall in sand and can't flip over
There's reasons to get sand too, it makes for a nice calcium buffer, gives lots of critters a home, and it just looks nice. On a bigger tank alot of people actually
feel a deep sand bed (or DSB) is the way to go. For a nano, however, I'd go barebottom or barely bottom.
I've seen REALLY awesome nano-tanks that used live rock rubble as a sandbed too, really nice looking and the current could still pass through the cracks and clear the debris. It's been a fight but I've had alot of success with my nano over the last 9 months. I've been keeping full reefs for years, had a 55g and a 75g before I moved... honestly the nano is more of a challenge than both
but worth every second and every penny.
Good luck to you, do some research on deep sand beds (DSB) and barebottom, I think you'll agree with me.