There are Web sites that meet by chance and which are the real jewels of these is a Rare Aquatic Plants.
It appears initially as a blog, with specific topics: the rare plants and aquarium Caridina. The approach is very professional and impressed.
browse through the articles you find that you need to read a full registration and from there you discover that you have access to a forum.
The forum contains a few recent posts ... seems very popular but I think the price to pay for a specific topic such as the rare plants. On the other hand the few interventions appear to be very specific and therefore more worthy to be viewed.