They need a tropical-style terrarium with live plants. 20 gallons should be sufficient for four adult frogs.
You have to know what species you're getting in order to design their enclosure appropriately. Terrestrials (such as D. azareus and P. terribilis) require a lot of floor space, while arboreals (D. ventrimaculatus, D. imitator, etc.) should be provided with extra height.
Juveniles should be raised in smaller, simple terrariums. 10 gallons is enough for six young frogs. Substrate can be any of the following: moist paper towels, sphagnum moss, or a soil mixture. You should provide a few hiding spots like cork bark curls, leaf litter and live plants. The water dish must be very shallow.
There is no problem with juveniles getting along, but when they become adults, PDFs are territorial. It's recommended to house them in male-female pairs instead of groups, but if you decide to house them in groups, make sure to have lots of extra room, visual barriers and hiding spots so they won't see each other all the time and can retreat if they get hurt in a fight.
They should be monitored daily to ensure each frog is healthy and getting enough food.
Temperature:
"Different species of poison dart frogs require different temperatures. Most of the common species offered for sale do best when kept between 74F (23C) and 82F (28C) during the day, with a drop down to around 70F (21C) at night. Some species from high altitudes need to be kept at much lower temperatures. During cooler months of the year a reptile heat pad can be attached to the back or sides of the terrarium to maintain the proper temperature. If a false-bottom style terrarium is being used, a high quality submersible aquarium heater can be placed below the false-bottom in the water to heat the terrarium. Heat lamps do not work well for heating terrariums that house dart frogs because they tend to dry out the cage."
The humidity level in the environment must be very high. To accomplish this, mist the terrarium with water three times a day. A glass top or screen cover with plastic wrap should be used to prevent the humidity from falling too low.
The hardest part of taking care of PDFs is finding a steady supply of tiny live insects to feed them. You can look around for places to order these insects from, but you can also breed them yourself. Fruit flies are very easy to culture. The flightless kinds are recommended.
Crickets (the smaller kinds) are another option. Also springtails, termites, rice flower beetles and aphids.
Feeding:
"The number of food items that are fed per frog each day depends on the size of the insect and the size of the frog. A large D. tinctorius can easily eat 50 pin-head sized crickets in one sitting, but if larger crickets are used they won't need to eat as many. Normally between 15 and 40 insects can be offered per adult frog every other day, although this amount will vary quite a bit depending on the size of the frog and the size of the feeder insect. Young frogs do best when offered food once a day in smaller quantities. Use high quality reptile vitamin and mineral supplements on feeders that are fed to the frogs frequently, with juveniles having their food supplemented as often as every feeding."
VITAMIN AND MINERAL SUPPLEMENTS ARE ESSENTIAL. You cannot skimp on this. Food sources must be dusted with them once a week. There are products specially formulated for dart frogs, but some keepers have reported using Rep-Cal and Herptivite for years with success.
An environment conducive to breeding must include:
+ Lots of foliage
+ High humidity
+ Breeding spots (lots of them)--- a cocohut over a Petri dish for large frogs, a film canister for small frogs.
To induce breeding you will need to trick the frogs into thinking their breeding season (the wet season) has arrived. Mist the tank once every other day for 2 weeks, and then follow that with 2 weeks of misting twice a day. However, they also usually breed right after a storm. Lessen the amount of feeding during the light misting, and increase it during the higher misting.
What to do with the eggs:
"Usually you will get a couple of clutches of eggs that will go bad and mold over. This is normal. Bad eggs will swell up and get cloudy. In developing eggs you can actually see the tadpole develop in the egg. When I get eggs, I take a paper towel, wet it, and place it in the bottom of a 24 oz Ziploc container. I then take the Petri dish and place it on the paper towel (I do not put the top of the Petri dish on Petri dish). I then add enough RO water to just touch eggs. If the eggs are laid on a film canister, I put the film canister on it's side on the Petri dish and add water so it just touches the eggs. Once I can see the tadpole in the egg I dump the eggs out of the film cannister into the Petri dish. Finally, I put the Ziploc lid on and mark the top with species of frog egg.
If you are having trouble with multiple clutches of eggs molding over, you may want to try spraying the eggs with Methylene Blue to reduce molding."
Tadpoles:
"When the tadpole's tail is straight, you know it has hatched. It is now time to take the tadpole out of the petri dish. I use a plastic spoon to scoop the tadpoles out. If the tadpole is too quick, I will sometimes use a turkey baster to get them out. I place the tadpoles individually in 32 oz fruit fly cups. I add 1"-3" of RO water and a small piece of Java Moss. After a couple of days, I fill the cup up entirely. If you do not have a Reverse Osmosis System, I recommend that you use some of the water treatment products.
I feed my tadpoles Frog and Tadpole Bites, 50/50 blend of Spirulina and Chlorella, and Tadpole Micro Powder. I feed 1-3 times a week and I NEVER do water changes.
Once the tadpole sprouts front legs, I pour out all of the water, get rid of the java moss, and add an inch or so of RO water back into the cup. I then use a dixie cup to prop up the cup. This creates a sloped area where the frogs can climb out. When I see a frog completely out of the water, I move the froglet into a froglet tub."
Froglets:
"Froglets get put into tubs in pairs. The tubs are a 190 oz container with sphagnum moss, some plants, and a film cannister. I seed all tubs with springtails so the froglets can have a variety of food. I feed all froglets every other day."