what to put in my new 12g

[doch]

Only thing that will become a problem is the clowns... they're pretty big for a 12. As for bio load, as long as you're skimming and doing regular water changes you should be ok to add a few more little critters. I suggest a yellow clown goby, rainfords goby, maybe a goby/pistol shrimp combo, and or a barnicle blenny. My barnicle blenny is one of, if not my favorite fish... he's wicked!! As long as you keep your purchases small, you'll be alright.