16 New Goldfish, Help With Set Up! Options

[Hamad]

Hello guys, I couldn't do this without your advice so here it is.

I am getting a box with 16 goldfish as soon as I confirm the order and send in the cash, it takes just one day for the box to reach me so I need to make sure everything is fine and set once the fish are here.

I believe that 16 fish will need 10 gallons each, a 160gallon tank is out of the question so I bought a 180 gallon plastic pool instead that I'll place in the balcony [it's much cheaper and the weather is ok now].

I am going to fill it with water today and then rinse it tomorrow just to test and then fill it and add aeration and have it ready for the fish. But what else should I add and should I treat the fish with anything? I would appreciate if anyone can give me very detailed information regarding this period such as how many water changes, how many times they should be fed, how much salt, etc...

Out of the 16 fish, 5 or 6 will move to the main 55gallon tank gradually [one fish every week], and any fish that doesn't look great to me I will sell to any of the local stores and just keep the best ones.

Thanks in advance!