It seems OK but i'm a little puzzled regarding your first chamber. If i'm looking at it correctly it looks like your first chamber gets flooded and overflows into your second chamber. So basically your first chamber isn't doing anything.
You could have varying degrees of coarse to fine sponges or filter socks in your first chamber and configurate your baffles so the water flows into the second chamber from the bottom, not the top. That first chamber will then be your mechanical side, not redundant as it looks from your diagram.
Maybe i'm not reading your diagram right, it's just that that's what it looks like to me the way you've planned it.