u/Ashamed_Address2620

We got a betta and kinda rushed into a new tank. Got a new 10 gallon tank, dechlorinated it, have a heater and a filter. Acclimated it slowly. After 3 days, it faded it color (red) and within hours was dead. We changed the water and dechlorinated every time. So, supposedly we didn't cycle the tank correctly. We took filter media from my daughter's 3 year established tank, put part of that in the filter on day one. Bought all the test strips, bought all the bottled bacteria, bought all the ammonia nutrilizer. Followed all the instructions. Except for cycling for 2 months or whatever ridiculous time I keep seeing. All strips showed all levels were where they needed to be. Got fish #2. Fish was great for 4 days ... Same thing happened, suddenly got pale, dead within hours. Both had a white fuzz that appeared right at or after death. My chatgpt was convinced the whole time that it's high ammonia. We did everything to avoid that. Here's the kicker .. my daughter brought home a betta from the same store the same day. She set up her old 10 gallon tank, with new rocks and everything else. She put part of her filter in there too. She put her betta in a simple one gallon tank with dechlorinated water, no heater, no pump or filter, for 24 hours, then put hers in her tank and that thing has had no problem. People bring fish home and set up the tanks every day and their fish live. By the time the second died, the tank had been set up for over a week. With filter media from an established tank, added bacteria from the bottle every day, added the ammonia nutrilizer every day.... What are we doing wrong? I know people say to 'cycle' the tank forever. Clearly people do it without doing that and the fish are fine. And all our test strips showed perfect numbers. Including the ammonia. I don't want to get anymore and sign it's 4 day death sentence. Help!