Changing Substrate

[KrystaK]

I'm changing substrate but I can't decide on what sort of substrate. I'll be using two options, as I have a 30gal community tank (Which could be any of the three options above) and a 5 gal Betta tank (Which will be either white sand or natural gravel)
I don't want both tanks to be the same substrate, but I cant decide.... When I first started I wanted black sand. So I bought what I thought was black sand online, as it turns out it's just a fine gravel (That is sort of sharp because my Cory's have cut their barbels(sp?) on it. So I want to change for their sake as well...
Anyways it was a black gravel and it looked fine, but i found it needed colored rocks on it to make it pop, it's not what I was looking for. So I was wondering if white sand would look better, if I should go out and buy actual black sand and hope for the best, or if natural looking may be the way to go...
I'm open to all three.... heck, I even have pictures below to help decide :

White Sand: (Which I'm paranoid will look dirty because of my messy fishies )

Black Sand: (I'm worried it'll be to dark looking and I'll need to add somethign to make it pop)

Natural Gravel: (I'm sort of wary of this in my tank because of my cory's and their poor barbels)

 

[Jay-93]

I think white sand just makes it that bit more impressive to look at. Better for spot cleaning too. Hard to do on black. If you maintain and clean your tank on a regular basis, I'd go for white sand