Hey there! If you are looking to keep a dart frog leucomelas are the way to go. They are great beginner frogs, leucomelas have great collors, a great call, very bold, hardy, and have personalities. Ill give you some basic information about keeping a dart frog (specifically the leucomelas).
Housing - The standard for dart frogs is 10 gallons per a frog. They may seem small but they are quite territorial. Dart frogs are kept in vivariums, which consist of a drainage layer, soil and real plants. The humidity for these frogs need to be 80%-100% all of the time. Therefore, a class lid will be required covering 90-100% of the top. It is recommended that there are many hides for these frogs. The easier the frog can hide the more often they will be out and about.
Water - Because the humidity is kept so high dart frogs do not require a watering dish/hole. Although, the water used for misting must be RO, distilled, or natural spring water (sorry well water wont work).
Temperature - Temperatures should be between 70-80 during the day (any higher and it could prove dangerous after a few hours) and can drop to 65 at night (i recommend no lower than 68).
Feeding - Dart frogs are best fed by the use of daily multivitamins powdered onto flightless fruitflies. They are very cheap and easy to culture. It is also recommended that you seed you vivarium with springtails and isopods to act as a secondary food source and cleaners. Although, it is important to not rely on the cleaners as a main food source.. just additional snacks for them.
Lighting - These frogs do not require lighting at all. I recommend a 12hr on/12hr off cycle. The lights are strictly for the plants alone.
I am short on time but continue researching! Any questions? I would be glad to help.