converting fresh to saltwater

[caleb]

I am going to convert my 10 gal. freshwater to a saltwater QT tank. The tank has been set up for 4 months can I use that water in the fresh water tank and just add Instant Ocean to make it saltwater, because it already cycled.

 

[beth]

No, sorry. It is cycled for FW not saltwater. Take a look at the FAQ Thread at the top of the forum for suggetions on setting up a QT. Likely you have some kind of rock substrate in a FW setup which you will want to get rid of for a SW QT.

 

[dgott2000]

dude that's really funny I have a 10g freshwater and a 55g marine tank and today I decided I needed to convert my 10g into a QT for a sick angelfish I have. I'm rather new at this hobby, but I'm pretty sure that the established bacteria for your freshwater tank is different from the bacteria necessary for saltwater. What I'm doing is a whisper 10 filter but instead of filling the mesh bag with carbon I put a bio ball from the filter of my 55g and then filled the rest with some live sand also from the 55g tank. I'm using water from the established tank and hopefully that will help speed up the cycling process too. If the ammonia or other chemicals start to build up I can easily do a 50% water change and add more water from the big tank. I hope this helps and good luck!
Dave