Saltwater to freshwater conversion???

[capo larzo]

Can an aged / mature saltwater biological filter be immediately transferred to a freshwater tank? Are the strains of nitrifying bacteria the same, or would the filter have to re-cycle?

I have an eclipse3 running salt and im thinking of switching that particular tank over to freshwater. If i did the cleaning and conversion fast enough, would the bio-wheel be established already, or would i have to wait for the entire cycle to complete itself. Obviously there would be a mini-cycle even if i were to do a thorough cleaning and kept it salt.

Any advice/help is greatly appreciated.

 

[swede]

i'm assuming that since you're changing from salt to fresh you will be removing lots of substrate and decor. this would be where much of your BB would be anyways, so removing it would definitely mean you will have to cycle the tank over. it may not take as long if you have the old biowheel, but keep in mind that unless you thoroughly rinse all the equipment, it will leech marine salt for a bit. I'm not sure what else you should know about converting salt to fresh since i've never done this and i have never kept marine

 

[fast lane]

They are completely different bacterial loads. Bacterial beds in a saltwater tank, won't last very long in a fresh, and vice versa. You're going to want to break everything down, clean it well, and start fresh (no pun intended).