New to Mantellas

[CinnamonPearl]

Hello. I'm looking to start a 20 gallon long enclosure for some mantella frogs. I'm choosing between M. baroni, M. betsileo, and M. nigricans. I'm leaning towards baroni since I like how they look best. Since I'm new to this area of frog keeping, I was wondering if anyone had any tips or information I could use. My questions are:

1. Which of these listed species are the best for a beginner?
2. How many times a day should I mist for them? I've heard twice daily.
3. What are some good plant species to keep?
4. What are optimal temperature ranges for those three species?
5. How much tank maintenance do they require? I read that I have to break down the tank once a week, which seemed a little ridiculous to me, but I want to make sure.
6. Do these frogs require a huge variety of foods?
7. How many mantellas can I keep in a 20 long?

Any other tips or information would be really appreciated. Thanks for looking.

[Mentat]

Have not kept Mantellas yet; but this is a good site with lots of information on them: Mantella Frogs.​ Suggest you add availability to your decision criteria as not all species are readily available .