Hitch-hikers......how long till I see em?

[kwirky]

My 120g's been up for 7 months now and tiny bristlestars are showing up now. Surprised me how quick they can move

I also have started hearing recently a loud smacking-against-something-hard sound in my tank about every 5 hours. If it's a mantis shrimp, it means I'll have to catch the bugger, but then I'll have a new excuse to set up another system