Not in your display, but yes you should still run them through treatment. The drug you want is not Furan but Formalin (pure Formalin, which is 37% formaldehyde). You should give them a bath and then transfer to your sterile QT, After transfer, another treatment period helps ensure you've cleaned them.
Formalin bath: 1mL/gal for 250ppm, for 30-60 minutes.
In QT prolonged bath: .1mL/gal for 25ppm, dosed every other day for 5 doses with 50% water changes inbetween dosing days, which makes a ten day treatment.
Aerate heavily with air stones in both the bath and in QT as formalin reacts with O2 in water. Good luck and I hope they do well.