Soak away help

d.r.w

Hello, I am digging a soak away and wondering what rubble would be best to put in it. 

My only two options are either broken brick (if so how much broke? Just in half?) or 20mm gravel?

thanks in advance

wild edges

You don't generally fill soakaways with rubble as it reduces the holding capacity by about 90% and silts up over time to even less than that. Have a look at plastic soakaway crates instead.