Flat $7.99 Shipping, Orders over $60, ship free.

Common Fish Diseases and How to Fix Them

Keeping freshwater fish is a rewarding hobby, but just like any pet, your finned friends can sometimes get sick.

We'll dive into the most common fish diseases you might encounter, their symptoms, and some easy-peasy solutions to get your underwater crew back in the swim of things.

Ich or White Spot Disease (Ichthyophthirius)


  • Your fish might rock white, salt-like spots on their skin, gills, and fins.
  • They could be scratching against stuff in the tank.
  • Less appetite and more lazing around than usual.


  • Turn up the heat to 78-80°F (25-27°C) in your tank; it'll speed up the parasite's life cycle.
  • Add some aquarium salt (1 tablespoon per 5 gallons) to de-stress your fish.
  • Go for a commercial ich medication, but be sure to follow the instructions.
  • Isolate the infected fish to stop the disease from spreading like fishy wildfire.

Fin Rot


  • Look out for torn, tattered, or rotting fins and tails.
  • If you spot any redness or puffiness around those areas, it's a red flag.
  • Your fish might also lose their appetite and get a bit lethargic.


  • Give your tank a makeover – better water quality and regular water changes are a must.
  • Throw a broad-spectrum antibiotic at the infected fish (not literally, of course). Maracyn works great.
  • Keep their diet balanced to boost their immune system.
  • Use aquarium salt at 1 tb per 5 gallons.



  • A pufferfish-like, swollen belly is a clear sign.
  • Raised scales that look like a pinecone.
  • Your fish will act sluggish, refuse food, and have pale gills and fins.


  • Play doctor – isolate the sick fish.
  • Tidy up your tank's act, and keep water quality top-notch.
  • Hit it with antibiotics if it's a bacterial issue.
  • Aquarium salt could help ease the swelling.
  • Dropsy is usually an end- stage symptom, not the disease itself. Its a tough one to come back from, and your fish may need to be humanely euthanized.

Swim Bladder Disorder


  • Fish acting like they've had one too many, swimming wonky, upside down, or at weird angles.
  • They might struggle to stay at the right depth.
  • Eating could be a challenge.


  • A shallow tank for the troubled fish can help ease their buoyancy blues. Tall plants can also serve the same purpose.
  • Serve up some peas (sans skin) for easy digestion.
  • Keep things pristine in the tank, and make sure their diet is on point.
  • This is also a difficult disease to bounce back from. Your fish could still live a long time with Swim Bladder disorder. Their longevity will depend on the accommodations you make for them.

Velvet Disease


  • Your fish might sport a dusting of gold or rust-colored spots on their skin and gills.
  • Rapid frenzied breathing, along with some serious scratching.
  • They'll look tired, often resting on the bottom, or on decorations.


  • Crank up the heat to 77-79°F (25-26°C).
  • Put infected fish on time-out to prevent spreading the infection.
  • Use a copper-based medication as directed. (not Invertebrate safe!)


And There You Have It!

Remember, it's always easier to prevent fishy diseases than to treat them. Keep an eye on your tank's water quality, quarantine new fish, and don't overcrowd your aquatic gang. A balanced diet and gentle handling go a long way, too.

So, fish keepers, stay chill, and your underwater pals will swim happily ever after! And if things get a bit fishy, consult with a fish-savvy buddy or a local expert to get things back on track.

Happy fishkeeping! 🐟🐠

Leave a comment

Please note, comments must be approved before they are published