Filter? Gravel? Sand?

[FriendlyFriendlyFish]

I did a 20% water change tonight in my 10gal and I 'vacuumed' the gravel. I noticed that there was a lot of debris that seemed to be trapped in the gravel. I currently have a power filter suitable for a 10gal but I am wondering if I should add an under-gravel filter as well. I was also wondering if anyone has any preferences or knows if sand is easier to clean than gravel? I find that stuff seems to settle in between the gravel but I have no experience with sand. I think there is more waste than normal in my tank right now because I am suddenly overrun with pond snails. One hitched a ride in on a plant I bought and the rest is history......I picked up a couple Assassins the other day so hopefully that will help get things back in balance. Any feedback would be greatly appreciated! 
 
P.S. has anyone ever use a Rocket Filter? I see them on Aquabid but I have never heard form anyone who has one.

 

[daizeUK]

With gravel you plunge the vacuum into the gravel and stir it up to suck all the debris that falls between the gravel.  With sand there's no need as most of the debris stays on top, you simply move the vacuum in little circles above the surface of the sand and it will create a mini vortex that sucks up the lighter muck on top.  Dead easy once you get the hang of it.
 
I keep two vacuum siphons, a narrow one for precision vacuuming in the nooks and crannies and then I swap to a bigger one for siphoning the water out quickly.

 

[Lunar Jetman]

With gravel you plunge the vacuum into the gravel and stir it up to suck all the debris that falls between the gravel.  With sand there's no need as most of the debris stays on top, you simply move the vacuum in little circles above the surface of the sand and it will create a mini vortex that sucks up the lighter muck on top.  Dead easy once you get the hang of it.
 
I keep two vacuum siphons, a narrow one for precision vacuuming in the nooks and crannies and then I swap to a bigger one for siphoning the water out quickly.

 
Just to add, its advisable to poke down in the sand and stir regularly to prevent any compaction from occurring. This helps stop the build up of any nastiness (gases etc) that could be fatal to your fish.

 

[KittyKat]

If you want to use an undergravel filter to remove crud, then you should expect to be running it in reverse (pushing water up through the gravel) as running it in normal mode (pulling water through the gravel) only pulls the crud deeper into the gravel, which would mean that you'd need to vacuum the gravel more.
 
On the other hand, it completely normal if crud falls through the gravel, so as long as your ammonia and nitrite are at 0 ppm, and nitrate is reasonable, you don't need to worry much about it.

 

[TwoTankAmin]

It also matters if a tank is planted or not. All the gunk down in the gravel is food for plants.

 

[FriendlyFriendlyFish]

Thanks for the advise everyone. I have a BN pleco and some snails in my tank, are both ok with sand substrate?
 
Also can I use an air stone with sand or sill it make the inside of my tank look like a sandstorm?