Acclimating From Brackish To Freshwater

[Mikaila31]

I just bought some blue eyed rainbows (P. signifers), that have been kept in brackish water. I'm trying to acclimate them to my freshwater. How slowly should I do this?

 

[Colin_T]

The easiest way is to have them in a tank with brackish water and each day change 10% of the water, replacing it with fresh water. After a couple of weeks the salt levels should be pretty low and then you can start doing bigger water changes.

The other way you can do it is to have the fish in a bucket with some brackish water and have an airline in the main tank. You have a tap on the end of the airline and put that in the bucket. You start water syphoning down the airline from the tank to the bucket. Use the tap to adjust the flow so the tank water is dripping into the bucket. 1 or 2 drops per second is fine. Have an airstone bubbling in the bucket and leave it to fill up with tank water. It should take about a day to fill up and then you can drain half the water out of the bucket and let it fill up again. Then move the fish into the tank.
Make sure you keep an eye on the bucket filling up because sometimes when the bucket gets full the fish can jump out. You can also have a flood if you aren't watching closely.

The more salt in the water the slower you want to dilute it.