You are certainly on the right track. Feeding is no issue. You will of course quarantine any new darts to make sure each is healthy, feeding and growing well before introducing them to the permanent tank. Darts are usually active hunters unless they are intimidated by a bully. About 4 of the more group-oriented thumbnail such as imitators or reticulatus would look good here. While the larger frogs will all climb to a certain extent, I'd limit them to 2 in a 20 tall, but it will probably handle 4 of either leucs, galacs or auratus. It may be too crowded for more than 2 of the competitive tincs, or azureus. In my experience, it would be good for a single pair of pumilios. The general rule of 5 gallons per frog is fine as far as it goes, but some species aren't good group frogs.
I use Rio 600 submersible pumps for water falls, or Maxi-jet 600 on their sides. I've never had much luck with the smaller pumps or little table-top fountain pumps. Water falls are a great feature for any species. Some of mine actually sit in the smooth, rock-filled pools and get right under the falls. They help a lot with the humidity or when you have to neglect daily misting. The whole set up of false bottom-waterfalls also mediates rapid temperature changes.
I've mentioned in another post about trying out rubberized coco fiber slabs designed for hydroponics in lieu of the usual false bottom. The link below that will lead you to some dealers. So far, the tank is set up, planted and running well. I'll be running it to make sure everything is growing and working for a couple of months before indroducing a pair of Azureus. (This is a 54 gallon corner bow, and has been a lot of fun to play with.)
Just use your own imagination and don't be afraid to deviate and invent, then share. You have the idea, so won't go fatally wrong, whatever you do.
I will sometimes cut out the eggcrate and fit in a plastic food container to form the pool and contain the pump. One punctures holes in this with a heated ice pick so the false bottom water circulates. It can then be filled with smooth rocks to hide the pump and make is accessible in case of pump problems. I hide the edges with overhanging flat rock. These are just ideas to play with-- no dogma intended.
Hydroponic slabs
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Patty
Pahsimeroi, Idaho
4 D. auratus blue
5 D. galactonotus pumpkin orange splash back
5 D. imitator
6 D. leucomelas
4 D. pumilio Bastimentos
4 D. fantasticus
4 P. terribilis
4 D. reticulatus
4 D. castaneoticus