However I would hope that the medication would "clean" up the plants as the fish are getting "cleaned up". And the fish may be less stressed (and stronger) for having plants to shelter in.

* To do this, we may need to look at the specific disease.

Velvet and ich may not be living off of the plants, they are parasitizing the fishes. But I'm sure some free swimming stages of those maladies have been caught by surface tension and moved tank to tank with those plants.

I think that is why one shop i used to know (gone but not forgotten!) used potassium permanganate to combat illnesses on the fish, in the water and on the plants.

That is another reason I'm intrigued by anthemintics such as Flubendazole is that they tend to treat the disease or problem (camallanus, velvet, flukes, hydra, seemingly hexamida) and not kill the plants or even the snails.

However NEVER leave the fish in any treatment way beyond treatment. Was reading where even Melafix can be a problem if left with the fishes for weeks beyond treatment.

May have to experiment with hornwort to see if it survives treatment by anything other than salt. ;)  A hornwort is found in Death Valley in a stream which may get three times as "salty" as the ocean!

That is why if the illness has either infected or at least been exposed to everything in an aquarium, sometimes it makes sense to treat there. The gravel, rocks, filter, heater surface and even the tank sides above the water, the underside of the tank top and maybe even the reflector - if that kind of lighting is there - may have all been touched by the organizms spreading the disease. Nets, feeding equipment (a splashed turkey baster? a dropped for container?), siphon tubes, gravel vacs, water buckets and the aquarist's hands are all possible transporters of those wee beasties.

Some of you guppylog regulars can skip the following, (you've probably heard this message too much) but that is again why the Q-tanks are so important.

In an attempt to make a comparison with computer jargon, we buy anti-virus software to check for viruses in e-mail, attachments, floppy disks and other storage devices. If the discovered virus containing document can not be cleaned up, our software asks us if the offending e-mail (or what ever) should be quarrantined (well what do you know - they may have gotten it from animal & plants husbandry people) or deleted. (That last one courtesy of Dr. Kevorkian.)

Quarrantine tanks are doing much the same hopefully in keeping maladies out by way of one month stays in that way station. That may still not stop internally traveling Hexamita type organisms or Camellanus unless they are given a prophylactic treament. (That is why I have a "largish" order in to Dr. Harrison.)

Sometimes it makes sense to even leave a plant in the bag for a couple of days - the poor boy's quarrantine - to see what drops off or if any hair algae shows itself. At the moment I have some new plants and a new pair of fish in at sort of double quarrentine tank. It is a bit of a mess, but I think it will be for the better. :)

That is also why professional aquariums use a sort of pro-active quarrantine by treating new freshwater fish with a salt water bath and a day or two in a tank with formulin. Marine fish get the freshwater bath. Plants may get the alum soak.

It is not a bad idea to treat the plants. If you know that the medicine will kill them (copper and many plants don't get along) it may be worth a different treatment for the plants (a terrificly strong salt bath for instance). In some cases the plants will just be tossed. (A bonfire has it's virtues.)

Other plants, Java ferns, Crypts, Annubas are so valuable (and tough) that I will try to treat them with the fish.

Oddly, Crypts may actually respond positively to copper when all of the other plants are buying the store.