Sorry I can't give you a definitive answer, I've not used that size grit, I've had 20/40 and -60 grit and both have worked well. Why not get only the play sand? It may be better than mixing two different kins unless you are looking for a "salt and pepper" sort of substrate.

 

Thanks, I appreciate the response. It was your original posts on other threads that lead me to the possibility of using blasting sand.

I'm partial to black substrate and fish store sand is expensive. I thought maybe just adding a bit of the play sand to the black might help?

 

You can its up to your personal preference on visual esthetics. Have you tried asking the store that has the 30/60 grit if they will get other grit sizes in?

 

I did and they don't.

UPDATE: So I rinsed it really well and put the 30/60 grit in the tank and added the corries. So far, so good. It is fine, but doesn't seem too rough and the filter is not blowing it all over the place. I just have to unplug it if I need to rearrange anything or use a siphon.

I'll have to figure out water changes with the fish and the sand. Practice, practice, practice.