Hi Maggie,
Its good to ask those questions. Often times when people ask about mixing different species together they get a reply with very basic do's and don'ts but with nothing explaining why you shouldn't do it or why you should.
Adult crickets are not viscious killers that eat dart frogs in one bite. Crickets will however eat pretty much anything that is offered to them vegetables, grains and live animals will all be accepted. A starving cricket purchased from a pet store will literally try to eat anything. If you were to feed a few crickets at night to the red-eyes but not all of them were eaten an adult cricket could theoretically find a dart frog in the terrarium and start nibbling on it. Crickets can cause pretty sever injuries, ask Andy over on the frog forum (I think it was Andy). His African bull frog got part of a toe eaten away by a cricket once, I'd hate to see what would happen to a dart frog.
The other problem with putting large crickets in a terrarium with dart frogs is that it would be stressful. Dart frogs are sensative animals and although they are easy to keep when you stay between a few important guide lines, things can go bad pretty quickly if they become stressed from venturing outside of those lines. A few insects as large as a dart frog wondering around and disturbing things in the terrarium deffinetly isn't going to be beneficial to the frogs.
Don't worry, I'm not going to kill you. A 270 gallon aquarium is huge. I'm sure that in a tank that size there would be some way to successfully house a few red-eyed tree frogs and a some large species of dart frog like terriblis or large tinctorius morphs. In a terrarium that measured over 6 feet long, 3 feet high and 2 feet wide (around 270 gallons) you could probably create areas for both species of frogs. Lots of arboreal branches up high, maybe even a seperate feeding container for the red-eyes to eliminate the risk of large crickets harming the dart frogs. So it probably could be done, but why do you want to do it? When you first think about it the idea does sound kind of cool, but what frog would be benifitting from it? Would you still be able to observe normal dart frog and red-eyed tree frog behavior when they would be kept together? Tiger legged monkey frogs are almost only availible as wild caught animals so you probably wouldn't want to house them with dart frogs.
I've always been under the impression that when housing two species together you want species that have very similar behavior. I've heard that a nocturnal frog will disturb a diurnal frog at night and vice versa. Species that are closely related and have similar care requirements generally are the only kind that can coexist together in the same tank for long periods of time and those are species that are active during the same time of day.
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Devin
devin@amphibiancare.com
www.amphibiancare.com
3.2 Dendrobates tinctorius 'Dwarf French Guiana'
1.1 Dendrobates tinctorius 'Powder Blue'
5.1 Mantella aurantiaca
2.1 Mantella crocea
1.0 Ceratophrys cranwelli
1.0 Bufo americanus
0.0.1 Salamandra salamandra
1.0 Ambystoma tigrinum
0.1 Chamaeleo calyptratus
0.1 Phelsuma dubia
1.1 Uroplatus ebenaui
0.0.1 Chrysemys scripta
0.0.1 Chrysemys picta belli
1.0 Terrapene carolina triunguis