Pimafix is made by the same mob as Melafix (Aquarium Pharmaceuticals). It is labelled as "an antifungal remedy for fresh and saltwater fish, rapidly treats fungal infections on body and fins AND also treats internal and external bacterial infections".

Other comments on the bottle include (in part, there is more)-  
"will not discolor aquarium water or sealant"

"Pimafix has been specially formulated to work synergistically with Melafix for a more effective treatment against fish disease and to promote rapid healing"

"Pimafix is safe for even the most delicate fish species including tetras, discus fry and scaleless fish, like clown loaches"

"Treating with Pimafix will not harm the biological filter.....is harmless to live aquarium plants"

Treatment course is: 1 teaspoon for every 10 US gallons (40L), repeat daily for 7 days. After 7 days make a 25% water change. Treatment may be continued if necessary.

Cost: In Australia,
a 120ml (4oz.) bottle cost me $17.35.
a 237ml (8oz.) bottle cost $21.95

My experience with Pimafix:
I first used it to treat a silver dollar who had patches the size of your little finger nail that had lost their shine and within 24 hours developed fungus (white). I tried a fungus cure during which time the patches worsened slowly. I think the fish had a bacterial infection on which developed the fungus.

I started treatment with the Pimafix and the fungus/sores were gone within 48 hours and the fish was brighter. In that tank were also neon tetras, a cory, a swordtail, a silver shark and many, many guppies - nothing died.

With the above success, I thought I'd give the Pimafix a try on the overstocked, dropsy infected, male guppy tank. Worked a dream, no more dropsy for over a month BUT it came back :(. The return may be just b/c of the overstocking (no new fish have been added except from my fry tank) or it may be because half the water I use in the tanks comes directly from the creek without any chlorine treatments etc. This and rainwater is the only water I have available and the rainwater has a very low pH.

In the meantime, many other treatments have been tried for the dropsy with no success.

Over the last week 2 more fish died from dropsy and then I found one dead in amongst the plants and on inspection it had it's tail half gone. I had already noticed one other fish, the day before,  with a split in it's tail so on further investigation I found one other fish who's tail was suspect. I had also noticed that day that a few younger fish were "hanging out" in one corner not doing much. Keep in mind that inspection of these fish is difficult to say the least b/c there are so many of them and if I put my head nearer the tank there they all come flying (well swimming actually) over and there is just one mass of moving fish.

So 3 days ago I started another course of Pimafix and within 24 hours all fish are so well and healthy, active like you wouldn't believe (Corys included) and I think the split tails are healing and those fish don't look the slightest bit sick. No signs of dropsy yet and that had been starting to escalate (I had been losing one every 2-3 weeks).

Anyway, just thought I'd see if any of you have used this Pimafix and your opinions.