My RBT 'nem split a few months ago and I've been meaning to sell it but haven't had time to address it until now. Here's what it looked like a month ago.
It has decided to wander the tank and is less bubbly now but in time should (maybe) bubble back up under the right conditions. It's parent 'nem has been bubbly for over a year now and has stayed put! Its base is probably 2" across and its tentacles stretche about 6" across when it inflates its tentacles.
$60.