Online Diagnosis

Probably one of the hardest things to do...

There are literally hundreds of afflictions that can effect the health of your fish. This website is intended to help the average aquarist wade through them to figure out what's going on.

Online Diagnosis

Online Diagnosis

This online program was created to help give you a summary of what's going on and to possibly lead you in the right direction twoards improving your fishes health. At the end of the question section of this program you will receive a diagnsis report that will attempt to try and figure out what's causing your fishes problems. It will also recommend some steps to help nurse your fish back to health.

Freshwater Fish - Most Common

In this portion of the site I'm going to ask you a few questions that will help knock out 80% of the most common problems with aquarium fish.

Dead Fish

Check for dead animals in the tank. If you find one, remove it immediately and inspect it carefully for signs of illness.

Dead fish can be caused by any number of things. Continue reading.

Water Temp

Check the tank temperature. Heat can kill fish in a hurry. Sudden changes in temperature - especially cooling - can prompt an infection.

Make sure your water temp is at a good number. Usually 72-80 degrees for most fish is adaquate.

Test your Water

Check your water parameters, you should do that on a regular basis. Check ammonia and nitrite levels, as well as pH levels. Also smell the water. It should have a nice earthy smell. Water quality is the culprit in many fish illnesses. Low pH and ammonia or nitrite poisoning will cause dark coloring in fish, an increase in skin mucus, erratic swimming and gasping for air.

Mechanical Problems

Check the pumps and tubing. Ensure that aeration is adequate. Make sure all filters are working properly. Filters can get clogged. Be sure the filter media is clean and doesn't need to be replaced. Cloudy water is a sure sign that there's a problem.

Feeding your Fish

Have you been feeding your fish a varied diet, regularly and not overfeeding? Very hungry fish will take bites of other fish in the tank. Also beware of overfeeding, which can change ammonia and nitrite levels radically.

Is your fish eating?

Watch for fish with poor appetites. This can be a sign of stress & diseason. It can also be caused by a number of problems, dominant fish, a new environment, a parasitic infection, inappropriate feeding, etc.

Read Streaking, Gills

Check to see if the fish has red streaking on skin or bleeding gills, and note whether a fish is gasping for air at the surface. In these situations, suspect ammonia poisoning, which has no cure. It's common in new and full tanks and causes permanent damage to the gills.

Fish Acting Weird

Watch your fish for abnormal behavior such as odd swimming patterns, refusing to eat, hiding more than usual, sluggishness or extreme aggression.

Rubbing Fish on Ornaments

Look for rubbing, flashing or jittery swimming in normally sedate fish, which usually idicates skin parasites.

Fish Swimming Weirdly

Check for head standing, lying flat, floating upside down or sideways and poorly coordinated swimming. These are symptoms of either a swim bladder infection or an intestinal obstruction. These problems are caused by overfeeding or by eating dry food too quickly.

Fish Color Changes

Check for darker coloration in fish, which can indicate chemical imbalances in the water, parasites or bacterial infections.

Bloated Belly Fish

Look at your fish for an abnormal size belly, white fungus on body, fins or mouth.

Disease & Tank Problems

Common Problems

(80% of all problems aquarium issues)
New Tank Syndrome - Is your tank new? Do you have cloudy water?
Ammonia Poisoning - Fins are torn, red steaking on body.
Vitamin Deficiencies - Scoliosis (Curved Spine), Reduced Growth, Lack or Loss of Appetite
Bad Water - Gravel washed this week? Add new water? See Ammonia Poisoning
Swim Bladder Problems - Erratic Swimming Position, Loss of equilibrium.
Physical Injury - From fighting, bumping into things, etc
Stress - Acting weird? Hiding all day? Not eating?
Walmart Syndrome - Did you buy your fish there?


(Usually visual things/bugs)
Anchor Worms - Tiny white-green or red worms in wounds, Frequent rubbing or "flashing".
Black Spot - Small black speckles on body.
Ich - Small white "salt-like" pimples on fins & body.
Skin / Gill Flukes - Fish gasps for air at the water's surface, gills covered in mucus.
Oodinium (velvet) - Fine grey-gold to whitish 'dust' on the body.
Parasites (External) - Large ugly sores on body.
Planaria - Small White Hairlike Worms in the tank.

Bacterial Diseases

(Mostly Internal Problems or invisable problems)
Pop Eye - One or both eyes protrude from the head in an unusual fashion.
Dropsy - Huge, Fat, Bloated Belly, Lethargy and loss of appetite.
Fin Rot - Fins turn Jagged or whitish and die back.
Hole in the Head - Small holes in and around the head.


(Usualy white foggy type things)
Cataracts - White or grey "foggy" eyes.
Cotton Mouth - White "Cotton like" fungus on the mouth.


"My Fish is ALIVE! Thank you so much for your wonderful interweb site..."
- Jack R.