Hi. I'm new to this forum and was wondering if anyone has any specific information about exactly when and how to convert to brackish waters for silver-tipped shark catfish. I bought these fish thinking they were fresh water fish then found they really aren't. But I really like them and, if possible, would like to keep them as long as I can. They (I have 2) seem happy in my 55 gallon tank with 3 pictus cats, 1 jelly bean cichlid, one rather large common pleco and 2 angels. They are about 2-2 1/2 inches long now. At what age/size do I need to move them to a brackish tank and how do I gradually convert the brackish tank to a marine tank so they don't get sick?