I would consider getting a QT or convert one of your FW
tanks, if you can. Doing a FW
dip will not do a lot, IMO
. It gets some of whatever might be on/in a fish, but it does not get everything.
You want to try and match everything up from the dip to the tank (temp and ph). I usually do 3 minutes, but if a fish is looking really stressed, I cut it short. Just did this last night with my two Chromis that survived the MV ordeal a while back. I pulled a 15g hex tank from the garage to use as my QT moving forward. Using Marex to treat, just in case they still have some lingering.