Welcome!
My best way to tell you how to do a red eye setup, is to show you what I have for mine, and describe it. So lets start out with a photo. *note, this is when it was first planted. It has grown in a whole lot since then.
Don't think darts, think tree frogs. You are thinking darts.
Rocks at the bottom for drainage. I top with a mix of organic potting soil and shredded coconut husk.
My bottom is covered in magnolia leaf litter where there aren't plants. I haven't had any luck growing moss. The frogs need lots of plant cover to feel secure which means the light can't get to the bottom to keep those tropical mosses alive.
They will need tall sturdy plants to live on and branches up high to perch.
As long as you don't over water, you won't have to worry about sucking out the water from the bottom. The plants roots will grow down there and they will take care of that for you.
The only water I have in there is a small water dish. They hardly use it. I mist once a day and this is pretty much where they get most of their water from. I'll water the tank (a good soaking) once a week for the plants.
Here is an excellent care sheet that will help you with humidity, temps and any other thing.
Amphibiancare.com >> Red-eyed Tree Frog Frog (Agalychnis callidryas) Care
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Rain chamber. Yes you will need one. Most people use the rain chamber to raise the tads so it servers for breeding and rearing. Here is a great example of a rain chamber.
http://www.herpcenter.com/video-Red-...eding-112.html
Once your frogs have laid eggs, you can remove them and keep the tads in the bottom. They raise like any other tad. You can feed them fish flakes, but I would really suggest getting a few water lettuce plants, some water hyacinth, etc.. They will need good filtration, but be sure to cover the intake tube with a filter itself so they don't get sucked in. And be sure once they start getting their front legs, to make some sort of land they can crawl out of.