Reusing QT tank for next batch of fish

Zoran · Dec 22, 2020

I have just completed 3 QT tank treating 3 tangs with copper and prazi. Now I want to use the same 3 tank for my next batch of fish to QT.

Is it safe to just empty the water and replace it with freshly mixed salt water and reuse the tank without sterilising It?
I want to save and used the media sponge in there since it would’ve have beneficial bacteria to control ammonia.

Maritimer · Dec 22, 2020

You can reuse everything without sterilization ... but keep in mind that along with any beneficial bacteria, there will be remnants of any diseases (ich, velvet, brook, etc) and the bacterial film that can consume Praziquantel in the tank / on the sponges.

~B.

Jay Hemdal · Dec 22, 2020

Maritimer said:
You can reuse everything without sterilization ... but keep in mind that along with any beneficial bacteria, there will be remnants of any diseases (ich, velvet, brook, etc) and the bacterial film that can consume Praziquantel in the tank / on the sponges.

~B.

Ah, but those remnant diseases are now in the DT anyway (grin). The prazi eating bacteria is a huge issue though.
The only time I sterilize a QT is when it had an incurable disease like a myxosporidian or something....
Jay

DaddyFish · Dec 22, 2020

I do flush my QT with RO between runs and then re-dose with seven days of Seachem Stability to restore beneficial bacteria. I look at it as a "freshwater dip" for the tank, without the extensive reconstruction required after a bleach cleaning.

Maritimer · Dec 24, 2020

Jay Hemdal said:
Ah, but those remnant diseases are now in the DT anyway (grin). The prazi eating bacteria is a huge issue though.
The only time I sterilize a QT is when it had an incurable disease like a myxosporidian or something....
Jay

If the fish had been in QT for say, 14 days, shouldn't they be relatively clean, while encysted tomonts can easily remain in the QT? That's the sort of thing I had in mind.

Glad to know what your sterilization regime is. I've got a feeling that I know _just_ enough to A: get myself into deep trouble and B: understand the immense value of your contributions here.

~B.