Fish identifier and health check
What fish is this? Identify your fish and check its health from a photo
What fish is this, and is it healthy? Upload one side-on photo: the fish identifier names the species, reads the signs of fin rot, white spot or clamped fins, says how urgent it is and gives a care plan.
Fish dying now?
Test the water first, now. Ammonia has no colour or smell even at levels toxic to fish, so only a test shows it; nitrite is toxic at low levels too. If the test shows ammonia, stop or cut back feeding and change part of the water with ammonia-free water. Then ask a fish vet.
The result
What the fish identifier tells you
One photo, one report, with the data to check in your water test: find out the species first, then what is wrong and what to do this week.
The fish, with how sure the match is and the features that set it apart from similar species.
Frayed fins, white spots, white tufts, clamped fins, a swollen belly or a milky eye.
From the photo: the water, an injury, a tank mate or an infection, and which water readings to check.
One plain call, with the reason.
- Okay
- Watch
- Treat now
Water changes, quarantine, and the type of treatment, used as its label says; never a dose.
What to note and what to ask, when an aquatic vet should look.
Method
How the fish identifier and health check works
- 01
Photograph the fish
Side view, glass wiped, tank light on, camera flash off. Fill the frame with the fish so the frayed fin or the spots are sharp.
- 02
Test your water too
Ammonia, nitrite, nitrate, pH and temperature. Fish problems often start with the water, so the report says which readings to check against the signs.
- 03
Get the species and the signs
The fish identifier names the species and reads the visible signs and the likely causes, then makes one call: okay, watch, or treat now.
- 04
Follow the care plan
Water changes, quarantine, and the type of treatment to use, used as its label says, with the point where a fish vet should look.
Photos
How to photograph a fish for identification
Side-on and in focus, with the fins spread if you can wait for the moment. Fish keep moving, so take several photos.
Do
Wipe the glass
Clean the front glass inside and out, so marks on the glass do not look like spots on the fish.
Tank light on
The tank light shows the true colours. Light from behind the tank turns the fish into a silhouette.
Side view
The whole fish from the side, filling most of the frame, with the eye and the tail in focus.
The problem in focus
Get the frayed fin, the spots or the tuft sharp; if they blur, retake the photo and run it again.
Don't
No flash
Flash bounces off the glass and hides the details.
Do not net it for the photo
Handling is a stress and removes the fish's protective mucus: wait for it to come to the front glass.
Not from above
From above, the fins and the belly are hidden.
Reference
What is wrong with my fish tank? Signs and what they often mean
Match what you see, then test the water: poor water quality is a common stressor that comes before many fish diseases.
| Sign | Often means | What to do |
|---|---|---|
| Tiny white spots on the skin, gills or fins | White spot disease (ich), a parasite | Treat now: an outbreak is an emergency |
| Rubbing, flashing, more slime, less appetite | Irritation, often before the white spots of ich show | Test the water and watch closely |
| White tufts on the body and fins | A fungus such as Saprolegnia | Ask a fish vet or an experienced keeper |
| Fins wasting from the edge inward | Fin rot, a bacterial or fungal infection | Check the water today |
| Fins folded against the body | Stress or illness: a healthy fish holds its fins out | Check the water today |
| Bloated body, scales sticking out | Dropsy | Ask a fish vet |
| Gulping and gasping at the surface | Too little oxygen or poor water | Test the water now |
- Sign
- Tiny white spots on the skin, gills or fins
- White spot disease (ich), a parasite
- Treat now: an outbreak is an emergency
- Sign
- Rubbing, flashing, more slime, less appetite
- Irritation, often before the white spots of ich show
- Test the water and watch closely
- Sign
- White tufts on the body and fins
- A fungus such as Saprolegnia
- Ask a fish vet or an experienced keeper
- Sign
- Fins wasting from the edge inward
- Fin rot, a bacterial or fungal infection
- Check the water today
- Sign
- Fins folded against the body
- Stress or illness: a healthy fish holds its fins out
- Check the water today
- Sign
- Bloated body, scales sticking out
- Dropsy
- Ask a fish vet
- Sign
- Gulping and gasping at the surface
- Too little oxygen or poor water
- Test the water now
Signs overlap: white spots alone do not prove ich, which needs a microscope to confirm, so test the water and look for a second sign.
Source: UF/IFAS Extension (FA005, FA006); RSPCA; Wikipedia (Fin rot), as of
Reference
Betta fin rot: signs, causes and first steps
Fin rot can be common in bettas. It starts at the edge of the fins and works toward the base.
A bacterial infection gives a ragged rot; a fungal one rots the fin more evenly and often leaves a white edge. Sometimes both are seen together.
Bad water conditions, injury, poor diet, stress, or another disease the fish already has.
If the rot reaches the base of the fin, the fish cannot grow the lost tissue back, and the disease may move on to the body.
Water issues are a very common root cause of stress and illness in bettas. A water change and raising the temperature into the betta's range are often the first step.
Accidental tears heal on their own; fin rot is the tissue between the fins wasting away.
Source: Wikipedia (Fin rot); PetMD (Betta Fish Care Sheet); RSPCA, as of
Reference
Betta fish clamped fins: healthy fins or a warning sign?
Clamped fins are a sign, not a disease of their own. Stress weakens a fish's defences and lets disease take hold.
- Fins held out from the body
- How a healthy fish holds them: no tears, splits, spots or streaks of blood.
- Fins drooping or folded
- A sign that something is wrong; check the water and the temperature first.
- Temperature
- One of the most important influences on a fish's immune system; a sharp drop hits hardest. Bettas are tropical fish and need a heater and a thermometer.
- Crowding and tank mates
- Crowding, aggression and territory fights are stresses too.
- Handling and shipping
- Netting, a move or a new treatment stress fish; note what changed, and when.
Source: RSPCA; UF/IFAS Extension (FA005); PetMD (Betta Fish Care Sheet), as of
Reference
Betta fish price is not the whole story: buying a healthy fish
Before you pay for a betta, read the fish, not the price tag. Fin rot can come from poor water in pet stores.
- Colour and fins
Bright, vibrant colour and intact fins, held away from the body.
- Behaviour
Swimming around the tank and eating well, not always hiding.
- Eyes and scales
Bright, clear eyes and smooth scales with no injury or fungal growth.
- A tank ready at home
A heater, a thermometer, a gentle filter, a lid and a way to test the water, set up before the fish arrives.
Source: PetMD (Betta Fish Care Sheet); RSPCA; Wikipedia (Fin rot), as of
Scope
What a fish identifier can and cannot tell from a photo
A photo can show
- The species, with how sure the match is
- Visible signs: frayed fins, white spots, white tufts, clamped fins, a swollen belly
- How urgent it looks, and which water readings to check
- A care plan: water changes, quarantine and the type of treatment
Only an expert with it in hand can tell
- A veterinary diagnosis: white spot and some bacterial diseases need a microscope or a lab test
- Medication doses: use a treatment as its label says
- Your water quality: only a test kit reads ammonia and nitrite
- A price or value of a fish
A fish name is the start. The fish identifier also reads the signs, says which water readings to check, and says how urgent it is and what to do this week.
Next
After the fish identification: what to do now
- 01
Test the water first
Ammonia, nitrite, nitrate and pH, and the temperature. Ammonia has no colour or smell, so only a test shows it.
UF/IFAS on ammonia - 02
Fix the water before you medicate
Poor water and crowding stress fish. Correct them before or along with any treatment, or the problem comes back when the treatment wears off.
- 03
Quarantine new fish
New fish, plants and decorations can bring white spot in. Keep new fish in a separate tank first, and do not share nets or hoses between tanks.
UF/IFAS on white spot - 04
Ask a fish vet
When fish keep dying, several are sick, or a fish has sores, tufts or a swollen belly, contact a vet who treats fish.
RSPCA on fish health
Free fish identifier: no card, no trial
Trying the fish identifier here is free. The form asks for no card, no account and no trial, so there is nothing to cancel.
Limits
What a fish identifier cannot promise
The fish identifier is not a veterinary diagnosis and never gives medication doses: use a treatment as its label says, and ask a fish vet when fish are dying or several are sick.
FAQ
Fish identifier questions
What fish is this?
Upload one clear side-on photo. The fish identifier names the species, with how sure the match is and the features that set it apart from similar fish, then reads its health from the same photo.
Is there an app that identifies fish?
This fish identifier works like an app in your browser, with nothing to install. Trying the form is free and needs no card, no account and no trial.
Can a photo identify a fish with certainty, or do I still need an expert?
A clear photo gives a species match, and the report shows how sure the match is and the look-alikes. For a disease, an expert may need a microscope: white spot, for one, is confirmed that way.
How do you cure fin rot in bettas without making it worse?
Start with the water: test it, change part of it and keep the temperature steady and warm. Fin rot often follows bad water, injury, poor diet or stress. If it spreads toward the fin base, ask a fish vet before you buy a medication.
What is the safest fin rot betta cure the check suggests?
Clean water and a calm, warm tank first, then the type of treatment the signs point to, used as its label says. The plan never gives a dose. Antibiotics can harm the filter bacteria, so test ammonia and nitrite more often while you treat.
Can I treat betta fin rot with aquarium salt, and how often should I use it?
Salt is one treatment type, but only for fish that can handle more salt, and aquarium plants may not tolerate it. Use it as the product label says, never by a dose from a forum, and ask a vet when in doubt.
Betta fin rot and aquarium salt: is it safe with live plants?
Plants in an aquarium may not tolerate the higher salinity, says UF/IFAS. Treat the fish in a separate tank if the main one is planted.
How long can a betta survive with fin rot before it becomes too late to treat?
There is no fixed time. Act early: once the rot reaches the fin base, the lost tissue does not grow back and the body can be next. Test the water today and ask a fish vet if it keeps getting worse.
What do clamped fins in a betta mean?
Clamped fins in a betta are a warning sign: a healthy fish holds its fins out. Stress from the water, a cold or swinging temperature, tank mates or handling is the usual cause. Test the water and check the heater first.
What is the best food for betta fish when they're sick or recovering from fin rot?
A sick fish may not eat, and uneaten food fouls the water. Feed lightly, remove leftovers, and keep the water clean while it recovers; ask your fish store or vet about the diet for your fish.
What happens right before a betta fish dies, and how can I tell if I'm too late?
Signs of a fish in trouble include not eating, sinking or swimming to one side, gasping at the surface and a bloated body. Test the water now and contact a fish vet.
How to tell if a betta fish is male or female?
They can look alike. One way to tell is the ovipositor, the tube a female uses to deliver eggs; differences show from about two months after hatching.
Can this fish identifier tell me if a fish is safe to keep or eat, or if it's legal?
No. It identifies aquarium and pond fish and reads their health. It does not judge if a fish is safe to eat or legal to keep or catch: check your local rules.
Is this diagnosis exact, or just an estimate I should double-check?
An estimate from the photo. Some diseases can only be confirmed under a microscope or with a lab culture, so double-check with a fish vet when it is serious.
Why should I pay for a fish app when I can just use Google or ask locals for advice?
Trying the form here is free. Search and forums give a name or many opinions; the report puts the species, the signs, the urgency and a care plan for your tank in one place.
Does a betta need a heater?
Yes. A betta is a tropical fish, and PetMD's betta care sheet calls for a heater and a thermometer even in a warm home, because temperature swings stress fish.
Do new fish bring disease?
They can. White spot comes in with new fish, plants, decorations or equipment from another tank, so quarantine new fish and do not share nets between tanks.
Something looks off in the tank?
Photograph the fish side-on and test the water. See what fish it is, what the signs mean and what to do now.