Northern Cricket Frogs tadpoles - success story with happy frogs! This might answer some questions about raising tadpoles/frogs for you!
Over the summer, my boyfriend brought home a bucket full of little tadpoles. We decided to raise them, as it was getting closer to fall and most tadpoles get eaten or die in the wild anyway. We set up my 5 gallon fish tank and filled it with gravel, a piece of cool treated driftwood, some bigger stones, some Cryptocoryne parva grass, and a filter. We've also added some java moss and one piece of uprooted seaweed that I found in a lake which has rooted and grown taller.
Oh, my boyfriend also brought some snails home with the tadpoles. There has been something like twenty generations of snails that have lived in that tank now. Snails are pretty cute at first, but they become a problem when they start getting into the filter. Seriously, we have a ton of snails now. Don't get snails.
Anyways, over the last three or four months, the tadpoles have flourished! Out of the thirty or so tadpoles, only one so far has become a fully grown frog (we named him Big Papa). The rest are on their way. About a month or so ago, we separated the smaller tadpoles from the larger ones into another 5 gallon tank at my boyfriend's house, so that the smaller ones would have an easier time getting enough food, and hopefully to give them all more room to grow. We also did this so that the bigger frogs which had started growing legs could live in a half full tank with access to land (stones). We have a wire mesh lid on top of their tank, since once they have all their legs jumping out is pretty easy (Northern Cricket frogs can jump up to six feet!).
The tadpoles have been fine eating boiled lettuce for as long as we've had them. I'll usually boil a few large leaves at a time. You want to get it so that the leaves are soft and somewhat transparent. If you have extra, they're easy to freeze and just plop back into the tank when it's time for dinner again. I think one of the main reasons people say it has to be boiled, is because the lettuce will just float on top of the water otherwise if you don't. These tadpoles are absolute pigs! They'll munch away at the green parts of the lettuce and leave the white stems, so I usually take the white parts out when they're done and replace it with a new piece of lettuce. One problem about feeding them lettuce all the time, though, is that the lettuce will turn the water a yellow color, like light apple juice. And they'e super pigs, so after all that eating, there's a lot of poop to clean. I try to clean their tank around once a week, siphoning out around 60% of the water (since it gets so dirty so quickly). At one point I bought some algae tablets, usually meant for plecostomus type fish because I thought it might be a cleaner food. But the tadpoles didn't really touch it. Also, maybe mine are picky, but they wont eat red or purple lettuce. It's strictly green leaf for them I guess.
It does seem strange that only one has become a frog. There are probably about seven others now wit their full back legs grown in. Perhaps the reason some of them are still so small is because they are being raised in a smaller environment than their natural pond. Another reason they might be so small is because they aren't as fortunate in their genetics, and able to survive in their little tank whereas they probably would have died in the wild. We're not exactly sure what we're going to be able to do with all of these guys once they're full grown. Ideally, spring will come soon enough for us to be able to release some of them back into the wild. I hope that their lives in captivity won't impede their ability to survive and thrive in the wild, but we figured most of them would have died as babies anyways. We'll definitely end up keeping several frogs, though. Northern Cricket frogs remain relatively tiny compared to other frog species, not much bigger than an inch, so we'll certainly have enough room for a good handful to live happily together in the 20 gallon tank.
Now, Big Papa (sometimes I just call him Frog) temporarily lives in a 1.5 gallon plastic tank. I added gravel and built up half the tank with stones and placed a thick piece of moss that I found in my yard on top of this. I threw in a few sticks; one for him to climb around on and another floating on the water for him to grab onto. I also eventually added a tiny submergible filter (which he loves to sit on top of) which helps to keep the water from getting too stagnant and dirty. He is adorable and I love him :>
Soon, my boyfriend and I will be building Frog a better home in my 20 long aquarium. We will be building up and carving out a pink foam background, covering it with layers of cement and dirt, to make Frog's house look super cool. We are also going to be working out a way to have the submergible filter (I think it filters about 30 gallons) work while staying hidden beneath a foam rock layer, so that it will look like a waterfall in the tank which filters the pond. I have some pothos (or philodendron) vines that I will be planting in the tank (they root very easily and are almost impossible to kill-- I even have some planted in my goldfish aquarium). I also have an assortment of mosses and lichens that I found in the woods. I figure, we found these tadpoles in the wild, so it probably won't hurt them to add plants found in nature. One thing about moss, though, is that the stuff is usually full of occasional spiders, tiny bugs, and larvae. Those are just frog snacks.
One important thing to know is that there is a major difference between catching a frog in the wild and trying to take care of it in captivity, versus raising frogs from tadpoles and caring for them as they grow up. Frogs caught in the wild are usually already pretty accustomed to the way they hunt and eat food. When suddenly confined to a small bucket or tank, these unfamiliar surroundings will make them either too nervous to eat, or feel too different for them to understand how to find food in this new environment. Frogs caught in the wild should be left in the wild, but if you're able to find some when they are tadpoles, you'll have a better shot at actually keeping them as happy pets.
I feed Frog wingless fruit flies that I can purchase at a local aquarium store. I covered the lid to his small tank by stretching a leg from a pair of nylon tights over top, because the small fruit flies were able to get through the vent lines in the original lid. I also bought some Repashy Superfoods "Calcium Plus" powder, which I dust the flies with before feeding them to Frog. This is really important for Frog's diet, because in the wild he would have a greater selection of bugs to eat, but in captivity the wingless fruit flies don't provide him with any calcium. Different frogs may need different kinds of supplements, based on what kind of bugs they are being fed. I haven't been able to find these flies in stores like Petsmart, but they are available to order online if you don't live near a specialty aquarium/amphibian store. The flies I buy come in a clear plastic container with a food culture at the bottom of the container. These flies have lasted me a long time. They grow quickly, live long enough to feed to my frog, and lay new eggs so that there are more as long as their food culture lasts. Granted, fly larvae is dis-gus-ting, and having had some very unpleasant experiences with maggots in the past, I was terrified of getting them on me the first time I tried feeding Frog. Now it's not so bad. I just open the lid enough for me to tap out a few flies (around 10) into the container with the calcium dust the the bottom. It's better not to over-feed frogs. As a general rule, their meal shouldn't end up being bigger than their heads. I feed frog every 1 to 2 days, depending on the amount of fruit flies that come tumbling out of their container (sometimes way more than I expect fall out).
I hope this information was helpful in case you have any concerns for your froggies. Big Papa is a wonderful little frog, a super good fly hunter, and pretty stinkin cute. He knows when it's feeding time and it's really fun to watch him jump around catching flies. He's called a Northern Cricket Frog, not because he eats crickets, but because he makes a quiet little cricket peeping sound sometimes at night when he's happy. His peep sounds like two little glass marbles hitting each other. He likes to chill in his pond and occasionally I'll find him napping beneath the philodendron leaves on his cozy moss. Frog is a super pet and I love him. Frogs can be amazing pets when they have a good home, it just takes some patience, time, and a little bit of money to give them what they need. <3