Hi Mark,
Its deffinetly an awesome experience to raise your own frogs from tadpoles. Right now I'm raising my 60 golden mantella tads in plastic sweater boxes with bare bottoms and a few clumps of java moss for hiding. I've tried gravel with other kinds of tadpoles and found it to make water changes more difficult but a nice thing about using it is that it gives beneficial bacteria a place to grow. I think in the conditions that you are keeping them in everything should go well but keep an eye on the temperature. They will develope quickly when kept at higher water temperatures but the emerging froglets are smaller. Idealy they should be kept at around 70F if thats possible.
I'm raising mine on a diet of about 2 parts Omega tropical fish flake, 2 parts powdered spirulina, 1 part Tetra fish flake - vegetarian formula and 1 part crushed Reptomin pellets, all of that is crushed up into a powder. One word of advice is make sure you have a large supply of tiny insects availible when they morph out. I've raised dart frog tads many times (azureus, auratus and leucomelas) and mantella froglets are just absolutly tiny compared to emerging dart froglets. Mine didn't accept fruit flies until it was 3 and a half weeks out of the water. Good luck with it all, let us know how it goes!
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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
1.1 Mantella crocea
1.0 Ceratophrys cranwelli
0.1 Hyla chrysoscelis or versicolor
1.0 Bufo americanus
0.0.1 Salamandra salamandra
1.0 Ambystoma tigrinum
0.1 Chamaeleo calyptratus
0.0.1 Chrysemys scripta
0.0.1 Chrysemys picta belli
1.0 Terrapene carolina triunguis