Can Filters Matured In Freshwater Transfer To Brackish?

[fatboy]

I'm considering setting up a brackish tank for mollies. I have spare sponge filters in my freshwater tanks and a fluval 104 which could 'donate' a nice buggy filter sponge to the new tank.

Will the bacteria survive the transition from freshwater to brackish (1.005 or so)? I'm not sure if I need to cycle the brackish tank from scratch or if I could simply transfer filters and add fish after a few days.

Any help appreciated.

 

[nmonks]

Freshwater to SG 1.005 seems to work fine. Go slow (over a week or so) doing small water changes each day, replacing 10-20% of the aquarium water with SG 1.005 water. Check nitrites a few hours after each change to see how things look. Should be fine. Once you get above SG 1.005 things become less predictable, but for mollies and "low end" brackish fish like gobies and livebearers SG 1.003-1.005 is plenty. There are even some nice salt-tolerant barbs and catfish you can keep in such a tank, as well as lots of plants.

Cheers, Neale

 

[fatboy]

Thanks, Neale, that makes sense.

By the way, I was wondering why your username was so familiar and finally realised that I ordered your book a few hours ago.