Adding substrate??

So I have super fine sugar sized substrate(mistake). I am having a hard time with green cyano showing up on my substrate because I can't get the flow right, if I point it to blow over te substrate it goes nuts and bam a dust storm. My question is can I buy some crushed coral substrate and add about a 1/2 inch over my sand that way I can increase flow over my sand? Or would that w a problem? It's on sale so I can get a lot for cheap, im also doing my 10 gal so I need to buy some anyway

 

I did the same thing on my 55g. I had to fine a sand that was blowing and I added abit bigger aragonite over the top. It great now. If you add big chuck like crushed coral, it might prevent you housing gobies successfully.

 

http://www.petco.com/product/112009...aspx?CoreCat=MM_FishSupplies_GravelSubstrates

Would this work?? This is exactly what my LFS sells,