Northemer, are you having the symptoms you stated? (swollen fingers, rash, sore joints)
If you have a swollen joint from a bacterial infection, go see your primary doctor as soon as possible. Joint infections are not something to trifle with. Untreated, they can lead to arthritis. And, any bacterial infection which leads to a rash should probably be seen by your doctor.
If you did catch something from your tank, it could be Vibrio vulnificans, which can invade through cuts.