Zebra danio swimming upside down

[Rob001]

Good day I have a 55 gallon tank ,I set the tank up three days ago
And I washed the beach sand,my water is still isn’t that clear yet,I bought 1 zebra danio and two mollies 3 hours ago from the pet store and now the zebra danio is now dead,it started with swimming upside down and I thought it will be better.I think the tank isn’t yet fully recycled
Please help

 

[FreshyFresh]

Welcome.

The tank isn't cycled at all unless you set it up with substrate or filtration that came directly out of a long established tank.

Read up on nitrogen cycle here. You can run with what you got, by keeping some zebra danios in there like you are. Feed very lightly and keep up on regular/often water changes. Do you have something to test water parameters with? What dechlorinator are you using?

 

[Sprinkle]

Tank will be not cycled in 3 days, tank cycling will take up to 6 ish weeks.
What are your readings for ammonia, nitrite and nitrate?
Do a 75% water change.

 

[NoahLikesFish]

Beach sand can’t go in a freshwater tank

 

[FJB]

Beach sand (washed) can go in a tank with mollies (especially some varieties), as some like alkaline, and even brackish water. For some, marshes are their habitat, with faily high salinity. But zebra danios won't be too happy at all.

 

[NoahLikesFish]

beach sand is live sand though

 

[NoahLikesFish]

Live beach sand can and will raise salinity the real live sand is treated to work for salt tanks only