Raising Dart Frog tadpoles is an easy and rewarding process that can be done by the average person at home. Several methods will be discussed below.
The most common method and the quickest way to set up a system to raise Dart Frog tadpoles is to use 32oz Deli Cups. These are the same size cups that will later be used to make fruit fly cultures, and easily found online. One tadpole per cup, about halfway full with Spring, Distilled, or Reverse Osmosis water. A small piece of Indian Almond Leaf and some sprigs of Java Moss can be added to each cup, this will provide both shelter and grazing surfaces for the tadpole. The cups should be kept so the water temperature is kept as stable as possible in the 68°F to 72°F range. Each tadpole will develop independently in its own cup ecosystem. A similar method to raise tadpoles individually in cups involves the use of a tackle box or craft organizer. This can allow more tadpoles to be raised in less space, however extreme caution must be taken to ensure that such small volumes of water do not foul.
Tadpoles being raised individually in cups.
The Cup Method can work for any Dart Frog tadpoles, and is advantageous in that it keeps each individual tadpole isolated. A downside to this method is the tadpole is kept in a very small volume of water. While the tadpole is physiologically fine developing in a small space (many species develop in small phytotelmata in the wild) care must be taken so that such a small volume of water does not foul. Small volumes of water are susceptible to change, and too much in the form of temperature swings or nutrient build-up could prove fatal for the tadpole.
This is accomplished by limiting the amount of nutrients that go into the system, as well as allowing the individual ecosystem to establish itself and naturally cycle the nutrients, a review of The Nitrogen Cycle pertaining to aquarium keeping will provide a greater understanding of these processes.
Aquatic plants and Indian Almond Leaf provide both shelter and grazing surfaces for the tadpole. Both also provide benefits to the water quality.
Feeding the proper amount of food to the tadpole helps ensure that too much nutrients do not enter the system. The tadpole should respond positively to the food once it smells that the food has been added. If the tadpole doesn’t actively engage the food after it is added make sure that the feedings are not too frequent, and that the food is something that is appetizing to the tadpole (there are at least two commercially available foods advertised as being specifically for tadpoles that are simply rejected in my observations). High quality sinking pellet/wafer fish foods, high in protein and low in ash, should be used. Hikari Mini Algae Wafers is eagerly accepted by most tadpoles. It is important not to overfeed the tadpole, as uneaten food can quickly foul the water. Uneaten food should be removed no more than 24 hours after added, this can be done with a pipette or turkey baster. The amount fed per feeding will increase as the tadpole grows, but will likely not be more than a kernel or two per feeding. The tadpole should be fed at a minimum once every two or three days, however smaller but more frequent (daily) feedings are most ideal. Again, ensure that uneaten food is removed.
Even just 1/4 of a Mini Algae Wafer provides more than enough food for this Ranitomeya summersi “Reticulated” tadpole.
Tadpole’s Water Maintenance:
Along with removing uneaten food any detritus that accumulates at the bottom on the cup should be removed with a pipette or turkey baster. Partial water changes of 30-80% can be performed weekly to help ensure that acceptable water parameters are maintained. Tadpoles should be kept in purified water, as tap water contains chlorine and/or chloramine, and well water can contain sulfides, all of which can be fatal to tadpoles. “Spring” water is purified water with natural minerals, and is suitable for tadpole rearing. Distilled and Reverse Osmosis (RO) water is extremely pure water, and would benefit from remineralization with a reconstitution product such as Seachem Replenish. This replenishes physiologically needed minerals such as sodium, potassium, calcium, and magnesium which play a role in metabolic processes and help maintain osmotic balance. These minerals also restore and maintain the General Hardness (GH) of the water, which buffers against swings in the pH. Regular water changes with remineralized water will help prevent physical maladies such as Bloat and Spindly Leg Syndrome! When doing a water change make sure the replacement water matches the temperature and GH/pH to prevent thermal and osmotic shock to the tadpole.
The time from when a tadpole hatches to when it undergoes metamorphosis into a froglet/metamorph varies based on several factors including species, water temperature, and nutrition. This development phase typically lasts 6 to 18 weeks for the majority of Dart Frog tadpoles. About halfway through this process the legs of the tadpole begin to grow. The hind limbs are visible from the start of this process, while the front limbs develop underneath folds of skin which keep them hidden from view.
The still-covered front limbs of this Ranitomeya sp. tadpole can be seen with this backlighting.
As the front limbs develop they can be seen under the skin, for a short while it appears the developing tadpole is wearing a straight-jacket! When the front limbs are fully developed they break free from the skin which was covering them. This starts the next phase of the tadpole’s metamorphosis.
This Dendrobates tinctorius tadpole has fully developed front limbs, which will soon break through the skin that covers them.
Up until now the tadpole has used its tail for locomotion, and it’s mouthparts to graze and rasp at food sources. To become an insect-eating land animal the mouth structure of the tadpole undergoes a change, during which it is unable to consume food. During this time the tadpole metamorph absorbs its tail to meet its metabolic needs. Therefore once the tadpole has popped out both of its front legs the feeding of the tadpole should cease. Also at this point the water level in the tadpole’s cup should be reduced to just a few tablespoons, and the cup should be heavily-tilted (almost to the point where it is laying on its side). This will create a gentle slope along the side of the cup on which the metamorph can crawl out of the water.
This Dendrobates sp. tadpole has just sprouted its front limbs.
Once the metamorph crawls out of the water it should be moved to a land-only grow-out container. Leaving the metamorph in the tilted cup for too long could result in death due to drowning or starvation. The metamorph often still have some tail left when it leaves the water, this is okay, and the amount of remaining tail at which the tadpole leaves water varies some among species. If the metamorph is staying in the water and it tail is virtually gone it may need some encouragement. This can be done by reducing the water level even more, and possibly even evicting the metamorph into its growout container.
This Phyllobates terribilis metamorph has completely absorbed its tail and in ready for land!
Other Rearing Methods:
In addition to raising tadpoles in cups individually there are several other methods. These methods and their Pros and Cons are discussed below.
Many species of Dart Frog tadpoles can be raised in a communal tank in which they are not isolated from each other. The reasons all Dart Frog tadpoles are not raised communally has to due with competition with one another, which at the most extreme level includes actual cannibalism!
At one end of the spectrum are Dart Frog tadpoles that must be raised in isolation. These include tadpoles of frogs in the genus Ranitomeya, which are well known to cannibalize their siblings. On the other end of the spectrum are frogs such as those in the genera of Phyllobates and Epipedobates. The tadpoles of these frogs can be easily raised together, and with the exception of vulnerable freshly hatched tadpoles, even different sized tadpoles of these genera often can be kept together. Somewhere in the middle of this spectrum are frogs such as those in the genus Dendrobates. Dendrobates are among the most commonly kept dart frogs, and their tadpoles can be raised communally given the proper set-up. While more tolerant of each other than Ranitomeya tadpoles, Dendrobates tadpoles still display competition among individuals.
Several methods to reduce this competition include providing as much space for the tadpoles, providing cover for the tadpoles, and providing plenty of food for the tadpoles. The container in which the tadpoles are raised should be as large as possible, particular emphasis should be placed on the length and wide, the depth is less important. Wood, rock, leaves, and/or plants should be used to provide cover, provide grazing opportunities, and to break up the monotony of the communal setup. When the tadpoles are fed the food should be placed in different and changing locations within the setup. This prevents any dominant tadpoles from securing a monopoly over the food.
This communal Dart Frog tadpole system uses modified power filters for biological and mechanical filtration.
In addition to the benefits a larger body of water provides in terms of stability it also allows the use of filtration or heating. The use of small Hang-on-Back or internal/sponge filters can exponentially increase the carrying-capacity of the tadpole system. It should come as no surprise that increased water quality can have profound effects on the growth, size, and health of the tadpoles. The same can be said for providing a stable tropical temperature for them to develop in.
While communal raising as described above provides many benefits to the tadpoles in terms of water quality there are some disadvantages. Besides some species of tadpoles not being able to be raised communally at all such as Ranitomeya, those species that can be raised together such as Dendrobates spp. still have the risk of being out-competed by their peers, up to and including being cannibalized.
In an effort to enjoy all the advantages of each method while avoiding all the disadvantages NC Dart Frogs came up with the MartinMorphisis Tadpole Systems. These systems allow the isolation of each tadpole into individual cubicles in a series of removable trays. The largest system has 900 cubicles, and all sized systems provide complete mechanical and biological filtration, with optional chemical filtration and Ultraviolet Sterilization. The system can also have temperature control to provide a stable development environment.
The customization of MartinMorphisis Tadpole Systems is vast.
The design features of the system, such as spray-bars, keeps required maintenance to a minimum. An 80% reduction in weekly maintenance time was gained upon system adoption. The MartinMorphisis Tadpole Systems completely eliminates any competition the tadpoles would otherwise experience, which along with the stable and optimized water parameters result in noticeably larger and faster developed tadpoles with reduced mortality.