Sad news after I posted this topic one of the fish died the biggest most be the oldest one I guess he was separated from his mate no other possible reasons because the other three are alive and enjoying
I give them food ones and change 80% of the water daily I will buy a filter soon
Can I put them inside a plastic container or is it dangerous for them
If the plastic container uses food grade plastic it will be safe.
Take note that the minimum size is 60x30x30cm (see link in post number 6 to SeriouslyFish) so a glass or acrylic tank may be more practical.
Ooof my suggestion would be to take them back to where you got them, buy a proper aquarium and let us help you set it up and get cycled ready for livestock. It's going to be hard on your daughter to watch her fish die one by one in that tiny box
This thread makes me so sad, because it's such a common occurrence. Parents buying what they think of as cheap, easy "disposable" pets for their kids, without doing ANY research on the animal before buying it. I just can't wrap my brain around doing that. Not even knowing what they are!!!
My parents drilled it into me that BEFORE we buy any animal, no matter what it is, that we must know what they need and have what they need in order to care for them properly before even considering actually getting the animal. Perhaps it's only because my parents are animal lovers and owned a pet store so saw what happened when people buy pets they cannot care for, but they certainly made sure I knew that the only responsible way to get a pet is to know how to care for them and have their habitat set up before they would even consider buying it for me. We had a lot of pets. The rule was that if we couldn't give them what they need for their lifetime, the answer had to be no. We can't provide what they need, so we couldn't have that pet, as it wouldn't be fair to the animal, and it would teach us bad life lessons.
Having a pet is a great opportunity for learning with kids. My folks made me do my own research, and this was in the days before the internet, so that required going through their own book collection, going to the library to get other books, and making lists. What type of cage/tank/environment do they need? Can we provide that? What foods do they eat, and are we able to get those foods? How would they get along or be kept safe from other animals we had? Are they social and need company of their own kind? Etc etc. So when I wanted guinea pigs, I had to learn about what they needed, and wait while my dad built a hutch for them, since they didn't like how small commercially sold hutches are. While waiting, I was made to learn as much as I could about guinea pigs. That was educational, and also demonstrated responsibility. My folks teaching me to be patient and responsible because taking on any pet was a responsibility, and not like buying a toy.
Doing it this way disgusts me. Don't buy a pet for your kids that you don't even know how to take care of yourself. You didn't have to buy them then and there, the adult thing to do is say "no, we're not buying these fish today, but if you really want some, we need to learn about them first and get their new home set up, then come back and buy them once we know how to care for them". Then do that. If you can't provide what they need like a larger tank, filter etc, then you tell your child "No, we can't buy these fish today" and explain why. Like how my parents explained to me why I couldn't have a horse, despite desperately wanting one! I was horse mad, but also too young to understand how expensive they are to keep, and the amount of wok involved. Of course I was upset I couldn't have one, but eventually I understood, and appreciated that my parents said no! And that they took me to horse riding lessons and bought me books about horses for Christmas and stuff like that in the meantime. I understood that I couldn't have a horse yet, but that maybe I could when I was an adult and able to provide what they need.
But you didn't do that. You bought them on impulse, and I want you to have no doubt in your mind - you killed these fish. Which doubtless upset the kid. And did not teach them how to responsibly acquire and care for a pet. It's a sad missed opportunity, and it's something that happens way too often. Some people say "it's just a fish", and replace it, and never learn the lesson themselves, let alone teach it to their kids. It's also not something that only happens with fish and small rodents. People impulse buy pets like dogs without researching them, then wind up dumping and rehoming them when things get too hard too. It's desperately sad, and so easily avoided by just using some common sense.