your right, water changing before you add the next dose is the best way to go
salt would be a big help as it helps speed healing by stimulating their slime coat and helping with gill function...it also is possible that it does cure some diseases but i wouldnt totally depend on salt alone...but it sure dosent hurt to use it with other meds
i usually use 1tbl per 5 gal
is it possible to q-tank the fish that is showing the spots?...you can possibly protect your other fish from this disease by doing so also you avoid trashing your biofilter
i just use a 20gal rubbermaid contanier....i can break it down and store all the equipment inside when i dont need it and when i set it up for the first week or so i just take media from my other tanks and squeeze them out in the q-tank filter...and its cycled
its a handy thing to have around and you wont be tempted to stock it because it isnt a real "tank"
it sounds like youve done a good job researching diseases and treating appropriately but sometimes diseases can be difficult to diagnose even for the most experianced fishkeepers so it possible that it could be something else
so i'd say continue treating as you are, add salt and get a q-tank if possible and see how it goes...he dosent seem to be getting any worse and that in itself could be a good sign
good luck and keep us updated
--liz
