I have a ten gallon set up and QT the fish, so far haven't had any problems and the fish have all survived. Even if the fish don't carry any disease or parasite, it seems like it doesn't hurt to give them a chance to recover from the stress of transport without having to deal with curious or slightly territorial tank mates. I wish I put the first purchase of plants in separate QT jars, the one anubias nana ended up being very sickly and the rhizome/ tuber rotted in the tank. Now I am afraid to put any other anubias plants in that tank. Would anyone like to post photos of their QT set ups for fish/ shrimp or plants?