Signs Identifying Possible Diseases

Abnormal Behavior

Breathing Difficulties- Flukes, Velvet Disease
Distress/off Colored- Cloudy Eye, Chilodonella
Fins Closed- Ick
Clamped Fins-Poor water conditions
Scratching/Flashing- Flukes, pH
Increased Respiration Rate- Chilodonella
- Gasping at the water's surface- Not enough oxygen in the water, increase aeration, check water for ammonia, pH level, and nitrites (ph chart, nitrite chart, ammonia chart)
Appetite Loss- Tuberculosis, constipation
Yawning- Toxic water, parasites, Rock stuck in the mouth
Loss of Balance, Unable to rise from bottom of tank- Swimbladder Problems
Sitting on the Bottom- Swimbladder disease, Flukes
Eating Bubbles- It could be the fish is trying to clear its gills. You would want to check the gills. This could also be caused from air bladder problems. (read up up swimbladder disease)
Spitting-more info here
Rapid Gill Movement- Flukes
Restlessness- Fish Leech(Lice)
Jumping- parasites, low pH, poor water conditions
Tired out Fish- Check the water's conditions, do routine water change, smell the fish food and check its freshness, check for any other signs or symptoms.
Swimming Awkwardly- Costia, Swimbladder
Swimming with mouth open- could be a foreign object stuck in the fish's mouth
Swimming upside down- this is usually signs of swimbladder disease
Rubbing body along gravel or tank objects- Ick, Chilodonella, Costia, Fish Leech, Skin Flukes, Velvet Disease
Fish swimming wild- Check ammonia level Ammonia chart
Fish is standing on its head- Intestinal worms, Kidney damage, toxic water (do immediate water change) female fish may do this when they become exhausted from the male's breeding attempts
Fish is standing on its tail- Exhaustion from spawning, toxic water
Laying or leaning to the side- Where is the fish's light source coming from?, toxic water, infections, parasites, lack of oxygen. The fish could be blind and cannot see the light to balance itself.

Worms, Spots, and Lumps

Black Spots- Black spots
Lumps-Various shapes- Tumours
Small worms- Skin Flukes
Worm like protruberances- Anchor Worms
Disc-like parasites attached to body & fins- Fish Lice
Reddish or white spots making patches- fish pox
Small white spots on fish's body- Ick
White spots only on pectoral fins and gill plates- male fish of breeding age will sometimes have these spots
Open sores located on fish- Ulcers

Abnormal Appearance (except spots, worms and lumps)

Cotton-wool like growths- Fish fungus
Color Changes-Water quality, pigment loss, Melanophore Migration
Bulging Eyes- read more here
Curvature of the spine- Internal parasitic worms
Emaciated- Internal parasitic worms, Velvet Disease, Fish TB
Emaciated/bulging eyes & skin defects- Fish TB
Emaciated/sunken eyes & pale gills- Blood flagellates, Copepods
Eyes appear Cloudy- cloudy eyes
Fine white threads- Columnaris
Edges of fins frayed- Finrot-Tailrot
Split fin-more info here
Excess mucous being produced- Check ammonia level ammonia color chart
Fin edges slightly opaque- Finrot-Tailrot
Fin membrane breaking up- Finrot-Tailrot
Fin rays disintegrate- Finrot-Tailrot
Fish appears to be wasting away-flukes, more info here
Milky Skin-pH plunges, parasites
Pinecone appearance due to scales sticking out- Dropsy
Redness of Fins- Check ammonia level, parasites, bacterial infection
Sunken eyes- Dropsy
Swollen abdomen- Dropsy, Internal Parasitic Worms
Inflamed patches- Costia, Skin Flukes
Reddish color in patches over the body- Inflammation
Skin falling away- Chilodonella
Ulcerated Body- Columnaris, Dropsy
Bubbles in the fins- This usually occurs when the water is full of supersaturated gases (nitrogen) and this creates bubbles that the fish will swim into.
Yellow brown to to greyish color- Velvet Disease
Feces Trailing behind fish- Constipation
White eye- read more here
White spots on head growth- this is seen in species who develop head growth. It may be some debrie, etc. that has become stuck in the crevices. So long as the fish appears to be healthy I suggest against treating. Take a Q-tip that has been wetted with some peroxide and rub it a little. DO NOT get any in their eyes or gills. You can try a water soaked Q-tip as well and try to dislodge it.