[patm]

The one thing no one has mentioned about the darts is, opposite of many species, they are in fact more difficult to care for in bigger tanks. Now, I dont think you'd have too much of a problem with bigger species like D. leucomelas, D. tinctorius, D. Azeureus (sp?), or D. auratus. But your smaller thumbnails would definately be out of the question in 50 gallons, although they wouldn't utilize the floor space anyways.

Also, I disagree with the previous comment about FBT being more active than PDF's. Again, your bigger, bolder species are constantly active during the day, and I would go out on a limb and say they're even more active than the toads.

-Pat