Hyposalinity while maintaining nitrifying bacteria?

[1979fishgeek]

Is it possible to reduce the salinity slowely enough to not wipe out my nitrifying bacteria in my external filter?

How low can I go to treat ick and not stress fish and filtration?

Thanks

 

[cmcoker]

Well you need to get down to 1.009 to kill ich (there are strains out there that can still survive this treatment) and you need to stay at 1.009 without ever creeping back up to 1.010. So definitely need to have ATO and calibrated refractometer.
Your bacteria will take a hit, but ir won't eradicate them, so monitor ammonia
Watch pH as well as this will need to be maintained to keep the fish happy.
Are you sure it's ich, and only ich? Seems like lots of mixed infections lately, ich and/or velvet.
I'd drop the salinity over a several days for the fishes sake, but they can handle drops down better than spikes up.

 

[1979fishgeek]

I purchased a powder blue tang and it developed ick....now my mimic tang has it too on its pectoral fins and only so long before the Sailfin tang and clowns show symptoms.

My own fault for not quarantining, I am upgrading to a 900l DS so going to transfer live rock, coral, inverts leave fallow for about 90 days and treat the fish in their old DS tank.

Then using a quarantine tank for all new arrivals from now on!

What would you drop the sg by each day?

Thank you

 

[Lasse]

Its normally the same type of nitrification bacteria in both fresh and saltwater – therefore probably nothing will happen with your nitrification filter even if you put it in pure freshwater.

For the fishes 8 - 10 ‰ is normally the critical point for both fresh water and salt water species. The salt content of a fish is just around 8-10 ‰ and at that point the osmosis will turn to the opposite physiological demands. Below that point the fishes has to conserve salt in the body and letting water out – over that point they need to conserve water and pulling salt out from the body.

Normally with reef fishes species you maybe not go lower than 16 – 17 ‰ but once my friend forget a clown fish in a fresh water dip for 5 hours – that fish I still alive (but in the right salinity)

I use ‰ -> same as Parts-Per-Thousand (ppt). here you have a conversion calculator

Hope this help you


Sincerely Lasse

 

[1979fishgeek]

Thank you!