When they are the sole fish you've, then no. Otherwise, quarantine both in the exact same tank before introducing them in your other fish. Thanks! We're happy this was helpful. Put your remaining 2 fish in the quarantine tank. Clear out your original aquarium and also have it cycle (Using https://erick4mzjs.blog-kids.com/32131305/the-ultimate-guide-to-how-to-isolate-tanks