changing a brackish tank to freshwater

cdawson

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How can I convert my brackish water tank to freshwater. Like actually emptying it out and using it for a freshwater amazon planted tank. What's the best way to do this?
 
You'll want to replace the substrate and filter media, but rinsing should work for th tank itself. Anything porous should be soaked in FW for a few days, with daily water changes. Things like heaters and the filter box will be fine with just a rinse. The tank will have to re-cycle (obvious, I know) with FW.
 
Oriongirl, I wasnt aware that there was any evidence that the bacteria in the filter media is different between freshwater and brakish or marine, and hence any need to change the media. I would be interested to learn if there is, as it is often queried as to whether to change the filter media when converting a set up.

Thom.
 
I can't document that the bacteria are different, and what I meant was that most media are porous (more surface area for the bacteria) and it would be very difficult to remove all of the salt from these surfaces. Trying to transfer it would likely result in a slow leaching of salts for a while. With how cheap media is, it just makes sense to replace it.

However--I don't think that the bacteria are exactly the same in both systems. The entire osmotic balance issue makes it unlikely in my mind, but short of setting up a FW tank, cycling it and then converting it to SW testing all the while, I can't offer any proof. Sorry.
 
Nitrosomas and Nitrobacter are SW, Nitrococcus and Nitrospira are the likely FW genera. Nobody seems to know where the change-over occurs in brackish, could be a range, could be different genera again.
 
The way I understood was for Freshwater, it's :
Nitrosomonas (ammonia) -- > Nitrobacter (nitrite)

And for Saltwater, it's :
Nitrosococcus http://www.ncbi.nlm.nih.gov/entrez/...ist_uids=12147525&dopt=Abstract&holding=f1000 (ammonia) -- > Nitrococcus (nitrite)

And currently, there is no article or book explaining bacteria colonies that exist in brackish water areas (as far as I know of)

Just in case you're wondering, I got the bacteria information from this link : http://www.fritzpet.com/article_nitbac.html
 
Nitrospira is mostly found in soil, they do however break down nitrite, but this topic will likely to be argued to death by scientists, as all the information I've found seem to have little variations.
 
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