Best info i could find for ya:
API Pro Series; FURAN- 2 (Nitrofurazone)- $5.99
(Furan 2 in capsules is no longer available)
*10 powder packets for 10 gallons each
* Effective against a wide variety of gram-positive and gram negative bacterial diseases of aquarium fish, including; Furunculosis (Aeromonas), Dropsy, Gill Disease, Fin and Tail Rot, Hemorrhagic Septicemia, Eye Cloud, Black Molly Disease.
CONTAINS 10 Powder Packets (Treats 100 Gallons)
*Can be combined with Kanaplex to make an even more wide spectrum treatment, especially for difficult cases of Columnaris or Aeromonas. This duplicates the popular Aquatronics product Spectrogram that is no longer available.
*Can be combined with Kanaplex & Metronidazole for parasitic, fungal, & bacterial infections; this duplicates the popular Aquatronics product Paragon 2 that is no longer available.
Most good Bacterial meds will damage BB a bit, but that is the least of you worries now. Fish are fine w/o BB if you have test stripes.