Hmmm... so I'm just being paranoid then. So long as no-one's had them colonize their stonies, I'll leave them be. I don't know how I'd go about removing them, short of a chisel, anyway.
Berghia?
I ordered mine online from the US... (
www.saltyunderground.com) the downside of berghia is that aiptasia is the ONLY thing they'll eat. So when you run out, they'll die. I'm about to redistribute mine throughout the Calgary region... they've increased in number and finished off all visible aiptasia.
Speaking of going off track... How are your pods doing, Kevin? Mine have fully colonized the sump; the glass is teeming with the little critters. Very happy with the tigger pods. Cash well spent.