When it it safe to add fish to a new QT?

1fastfxr · Dec 29, 2020

Hi everyone. So I'm a newbie and thought I had done all my research and had this aquarium thing under control, boy was I wrong! Thinking that I was nearing the time to set up my main display tank, and of course being new and not wanting to waste any time fishless after a bacteria in a bottle jump start to the tank. I started my QT, adding the recommended dose of ammonia and using bacteria in a bottle also. After 2 days ammonia disappeared and nitrite began to rise and fall to a low of 5ppm. The Nitrate climbed to 10ppm. The nitrite just would not go away and the Nitrate just sat stagnant. My lfs told me to do a 50% water change and add fish. So I added 6 green chromis ( I now realize that was alot). Ammonia rose once then disappeared. But the Nitrite and Nitrate remained constant at 5 and 10 ppm respectively. Within a month all 6 fish had died. Then, life got in the way and the tank sat fishless since the end of July till now (5 months) with only adding rodi. Today I checked the parameters and ammonia is 0, Nitrite is 0, and Nitrate is 40ppm. Does this mean i can do a water change and add a fish? Or should i just tear it down, steralize it, and start over? Obviously , the display tank is ready for water, so I'm anxious again. Any help is GREATLY APPRECIATED!

Sailfin11 · Dec 29, 2020

Hey there! I wouldn't worry too much about measuring nitrite and nitrate, most hobby test kits are not that accurate anyway. Since your QT has been set up for a while, it should be cycled and ready for a fish - I'd recommend a clownfish or damsel. You are right on, I would do a 50% water change first and then you should be good to go.

1fastfxr · Dec 29, 2020

Sailfin11 said:
Hey there! I wouldn't worry too much about measuring nitrite and nitrate, most hobby test kits are not that accurate anyway. Since your QT has been set up for a while, it should be cycled and ready for a fish - I'd recommend a clownfish or damsel. You are right on, I would do a 50% water change first and then you should be good to go.

@Sailfin11 Thanks for your input. I was hoping to start with more timid fish? What do you think of a royal gramma and a fire fish in the QT? Do they have a chance of making it thru?