Congratulations Dorothee, great news and with so many fish dispersed around the mainland, hopefully more Paro friends will join in with your success and a healthily diverse breeding stock can be maintained.
Helene, your small problem with large numbers of Tweediei juveniles to pass on could be eased should you ever visit us here in the UK 😉
I too find that small tanks (<10L) with single pairs are more successful. If courtship behaviour is not present after a short time or has subsided, I will use the opportunity of a water change to separate out both fish, re-scape the tank (moving the filter and heater too) and reintroduce the fish one at a time(female first, male one hour later). This method has not always produced successful mating, but never ceases to switch on courtship in the male fish in my experience.