Hopefully the new tank will be way more heavily planted that this one is, it was basically messing around to see what works. I love the "grassy" look so I'm going to focus on vals and dwarf sag as background and foreground respectively. Thinking I might try just an area of sand in the front with the STS all in the back and sides (and eventually under plants hopefully!). Likely it'll all get mixed eventually but that's ok. Worst case is that the sand is on the bottom. This little experiment was mainly to see what it looks like if the two mix on the surface, and it looks good to me (like a riverbed).
I'm just too darn cheap to fill up a big tank with hundreds of $ worth of sand just because it's the right color (caribsea natural etc).