[odin]

another question: since there was no time to let the tank cycle, I do have to Keep an eye on nitrate, don't I?
and maybe be extra careful with adding food?
and also doing water changes regularly during the next weeks in order to get any nitrite/nitrate out?

I bought the mixed water in the petshop and, as I maybe earlier mentioned, they said, "it is ready to put in fish". But I read, that the bacteria don't float in the water, but mainly live on the Substrate and rocks and in the filter, is it true?

You will need to test the new tanks water for ammonia, nitrites and nitrates and if you pick these up you will need to do a small water change and test again and see how much there is again, you really want zero ammonia zero nitrites and very low nitrates (10ppm or below). I wouldn't feed them for a while and when you do maybe once a fortnight and a tiny tiny bit only! What SG (salt quantity) is the water you have added to the new tank form the store?

[fredanddino]

I mixed the water from the petstore, since it was marine water with about 1.030, I mixed it with distilled water down to 1.018

thank you, I will watch the NO2, NO3, Ammonium, wait and see

I will tell you in a couple of days (or weeks), if they made it.

THANKS TO ALL for your help, first days I ran around like a chicken with no head and your support was really a big help

[odin]

I mixed the water from the petstore, since it was marine water with about 1.030, I mixed it with distilled water down to 1.018

thank you, I will watch the NO2, NO3, Ammonium, wait and see

I will tell you in a couple of days (or weeks), if they made it.

THANKS TO ALL for your help, first days I ran around like a chicken with no head and your support was really a big help

No problem, keep us updated and ask if you have any more questions, we are here to help!