Fish Healthy - Vertical Swim - Cork Screw Swim - Dye
I am at complete Confusion.
History: The tank has been established for years containing fish that is over 8 years old and I have not changed cleaning habits.
A few new fish were introduced here and there in the past few years.
I have a healthy looking tank, then one fish will start to swim vertically then swim in a cork screw, a day later is dead stuck in the plants. Days weeks go by and all looks ok, then suddenly another fish will go into the same cycle. This has been going on for a while just one fish at a time.
My question is &%$#@*^!!
It must be a parasite or bacteria correct?
What should I treat the tank with?
My Next step is I am down to four fish; I will toss all filters and plastic plants out and treat the tank, moving the water with a water pump.Starting new with filters and decor.