If anyone has experience with java fern galls, I’d love to start a discussion on it.
I don't have experience with it, and actually had not heard about it until your post, but Dennis does have a short article regarding the disease. Looks like
Java Fern Gall Disease is actually a fungus, which explains why it can be persistent. The spores of many fungal pathogens can be notoriously difficult to kill. If the spores are dormant in the rhizomes, even removing all of the leaves of a new java fern, and planting the rhizome, can still spread the disease.
For restarting a tank, after tearing it down, there are products out there that would be effective saniziters, like some of the triple-phenolic disinfectants we use in hospitals, but unfortunately they would not be safe for sanitizing aquarium equipment with because those compounds can readily penetrate silicones and plastics, and leave residues that would be harmful to aquatic life. Although they would be good for sanitizing things like stainless aquascaping tools between uses/tanks, providing they are very well rinsed and dried.
Chlorine may require higher concentration, and contact time, but has the advantage in our hobby that it can be neutralized effectively.
I do wonder how many hobbists that have torn down infected tanks and had the disease return, accidentally cross-contaminated a restarted tank. Using the same pinsettes, or water change hoses between tanks. I think you would have to assume that if any equipment, hoses, media (when cycling a new tank) etc are shared between tanks, that they are all potentially contaminated. Because this fungus has a motile zoospore phase, cross-contamination is highly likely. Dedicated maintenance equipment for a new/restarted tank would be the best practice to try to prevent reinfection.
That said, if you restart the tank, and sanitize all hard surface equipment, discarding all media, soils, plants, etc., I would be very tempted to only use Java Fern species from some of the newer tissue cultured java ferns becoming available through vendors like
Tropica.