Rosieinthegarden,
For the fish they may be the Metriaclima sp "msobo" African Cichlid. The fish start out as yellow; the males then develop various patterns. You might try calling the dentist's office to inquire. The receptionist may not know the answer but whoever tends the aquarium should know.
We have some All Things Plants members who live in Belgium:
JonnaSudenius and bonitin are two screen names I can remember.