Are my GSM's spawning?

[AliKat]

I can't find my Clownfish book anywhere, but I'm sure someone on here has experience with mating GSM's.

The female has been going around stirring sand up left and right, and the male (who usually stays close to the female and the anemone, keeps going behind a piece of live rock.

What should I be looking for? For those of you who place spawning tiles in your tanks, where do you put them? And what size tile do you usually get?

 

[Toddrtrex]

I haven't had GSM's for years, but when I did I had the tile right in front -- placed it over the spot that they were laying the eggs on. The tile size was the standard bathroom tile, maybe 5*5.

Can see the tile here -- with freshly laid eggs.