Unfortunately this is a common form of infection in livebearers such as mollies, swordtails, and platys, and it can be quite difficult to treat. I am very familiar with this condition. There are 2 treatments I have had some luck with, but neither is safe for all species of fish.
Can you please list what other animals are in this tank and how many of each? Knowing your water params is going to be vital for treatment... so you will need to get ammonia, nitrite, nitrate checked asap. If you don't have the kits at home then possibly you can take a water sample to a lfs? (Water must be tested within an hour of removing it from the tank to get an accurate result) If the lfs tests your water ask them to write down exact numbers for results. If they tell you "its fine" that does us no good and will not help at all.
Once I know what your water params are then I can suggest a medication that is safe and should work for you. In the mean time, get some carbon back into the filter and do your water changes to remove the Quick Cure. Quick Cure cannot be mixed with the other meds.
Mike is correct that this is bacterial based... but unfortunately the particular strain of bacteria that is responsible for this condition is very resistant to most medications that the livebearing fishes can handle.
I am also going to agree with Mike in saying that you will surely need a quarantine tank to treat this unless its safe to treat the entire tank. I noticed you mentioned frogs... which tells me that no med is going to be safe to put into the main tank. Floating an unfiltered bowl in the main tank is not going to work for this type of treatment, so be sure to get a heater for the quarantine tank as well.
And, lastly... Mike is also correct that this condition is highly contagious to other live bearing fishes such as mollys, platys, and swordtails.