Extremely small gravel-is this a problem?

[Endless Ocean in My House]

There aren't great places near me where you can get aquarium equipment, so I ordered gravel online. Now that I have it, I'm noticing it's EXTREMELY small. It's very fine, like sand, and though it says gravel on the back (with the usual advice to rinse it off) and appears to be gravel, the pieces are so small and thin I'm concerned. Does this really matter? I have an undergravel filter, but I wasn't sure about using it anyway.
Can I use my undergravel filter with such small gravel?
Will I likely have problems with this gravel when I use a gravel vacuum?

My tank isn't up and running yet and it's not too late to get different gravel--but it's going to be a pain to send this back and my budget is tight, so if I can make it work I'd like to.
Thanks!

 

[ccCapt]

Is this for a saltwater system? If so, scrap the undergravel filter before you even start.

 

[Endless Ocean in My House]

Yep-and okay, I haven't heard much good about the undergravel filter, time to get rid of it. As for gravel vacuums, such small gravel won't be a problem?

 

[David S]

If its sand size then its better than larger gravel which is a haven for detritus build up unless cleaned often.