Sorry to hear about the loss Adodge.
It is for that reason I am picky about letting people collect stuff I sell on trade me from my home. I get most to collect from my work place.And ones I do allow to collect from home, I never allow them to see my fishroom without me knowing who they are. ( so if you have seen my fish room, count yourself privelidged, LOL)
We dont really have a LFS here in Wanganui so people may find it easier to help themselves if they know you have what they want.
As LA said, you cannot accuse someone, but you can tell people you have reasons to believe. Was it through selling on trade me that you believe it to be this person??
And David, I too have the same fear about someone thinking I have Hydro setups. Though its mainly my neighbours who I worry about, so on many occasions I have left the curtains open at night while the light are on. If they are/were curious, Im not stopping them from seeing what it really is, although the countless Aquarium Paraphinalia around my yard, kind of gives it away. LOL