Both tinctorius and azureus are extremely territorial, and actually some people consider them the same species, so it depends upon the amount of territory you can provide, of course. In the usual hobby space, nothing is enough to keep more than a pair of them without an issue, or at least only one female to a couple of males. The females are the wicked ones. I'm not sure if this is an "all other frogs suck" situation or just the fact that some other frogs may attempt to use the same territory. Since a rain forest is vast, at best, we are crowding them. Many meters of space become inches, so what may get along in the wild in the same "territory," becomes very condensed. The so called "arboreal frogs" that tend to stay in the upper reaches, and terrestrial frogs, that more or less tend to stay on the ground, will both utilize all the space up and down and side wise in a hobby tank.
Saurian (Patrick Nabors) is the breeder I've purchased most of my frogs from, not only reliably, but totally honestly when one single problem occurred once with a shipment that was screwed up by a delivery service which had previously been reliable. The frogs were replaced at no cost to me, but at great cost to him. I have always experienced personal follow-up and advice. There are certainly others, such as Black Jungle, which has never disappointed, either. I have simply not ordered from some of the others yet, but in general most established breeders are reliable and guarantee live, healthy delivery. Just avoid the casual "bargain bin" sellers that will occasionally advertise, but not sponsor dart frog sites.
I have no experience with E. tricolor of P. bicolor, but a lot with D. galactonotus, especially the orange (95%) which is my favorite of all dart frogs. They are wonderful groupies, are bold and have "personalities" bordering on "intelligence" as no other frogs I keep do, except perhaps D. imitators in a group. Even with them, the larger the space, the better. I'm currently keeping 6 in a 135 gallon paludarium with an aquarium section. They are all over the place, including some swimming and exploring the tops of the aquatic plant leaves.
I'm currently doing my first mixing attempt in a 180 gallon paludarium with Ancon Hill auratus on one side of the aquarium section lagoon in the middle, and yellow galactonotus on the other. They will no doubt eventually explore and cross over once they get established. But both species are relatively non-territorial and do well in groups among themselves. They are very unlikely to hybridize.
If you do mix, be prepared to pull out any frogs that appear to be stressed or intimidated, and destroy any eggs that may be hybrids or mixtures between two different color morphs of the same species. This is more of an ethical obligation than anything. The general consensus among most dart breeders is to preserve the original lines as closely as possible in lieu of the declines in the wild populations. Most frown upon the creation of "designer dart frogs." The originals are quite beautiful enough, and are bordering on "endangered" in the wild. There are no written rules or dogma about this, at least not yet, but most serious breeders and hobbyists frown upon it.
I personally think a 40 gallon breeder tank is too small to mix any two species in. I'd go with a group of 5 or so leucomelas, P. terribilis, P. vittatus, D. galactonotus, or even some auratus of your choice, all good groupies, but not mix two species together. With a few bromes on the background, even a group of 5-6 imitators or intermedius would be very entertaining, especially since they raise their own young and their breeding activity and interactions are a hoot to watch.
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Patty
Pahsimeroi, Idaho
D. auratus blue, auratus Ancon Hill, galactonotus orange, galactonotus yellow, fantasticus, reticulatus, imitator, castaneoticus, azureus, pumilio Bastimentos. P. lugubris, vittatus, terribilis mint green, terribilis orange.
