RED SPOT ON GUPPY – Learn the Causes, Symptoms and 1 Week Accurate Treatment

The red spot on guppy or the other fishkeeper called it open red sore can see obviously in any ornamental fishes especially in the guppy fish. It is red blood wounds in the skin of the fishes. The red spot is caused by a bacterial infection, parasites, and poor water conditions.

For a newly set-up tank and does not develop any beneficial bacteria, it is better to use a water conditioner that is available in any aquatic store. The water conditioner helps to remove the harmful chlorine, neutralizes chloramine, creates clear water, buffers pH levels, helps the fish recovers from stress, and avoids the high ammonia level in the water.

Fish food is essential to our guppies especially if the fish food has mixed garlic content. It prevents sickness and diseases for our guppies. So it is better to choose the best fish food for them and they will be healthy and live long.


Red Spot Causes on Guppy

The red spot on guppy is caused by poor quality water that starts to develop high ammonia levels in the water which can result in our guppies have sick, stress, or even death. The poor quality condition of the water is one of the reasons caused by ammonia burn or poisoning. 

Overfeeding and fish poop will be converted to a high ammonia level of the water. So if we didn’t remove immediately all the decomposed material to your tank it will result have a red spot or other diseases of your guppies.

It is also caused by poor filter media. The filter media helps to filter all the decomposed waste like dead fish, unconsumed fish food, and poop inside of the tank. Good filter media helps to fight ammonia.


Red Spot Symptoms on Guppy

The common symptoms of red spot on guppy which infected by red spots are skin sore, reddish fins, and tails of the guppies. These kinds of disease are easy to cure and the mortality rate for our guppies are too little. However, if you ignored them, it has a high possibility that your guppies will have died soon.


Guppy Red Spot Treatment Infographic

Remember that to prevent the illness of the guppies will depend on how you give time to cure them. The most important is to isolate the suspected guppies to their community or during their guppy breeding to avoid the other guppies will be infected.

Success rate: Estimated of 90%-95%.

Day 1:

  • Isolate the guppies infected by a red spot to a hospital tank with stock/old water. 
  • Then add ¼ teaspoon of rock salt.
  • Do not feed your guppy.

Other option 

  • If your guppies are already alone in your tank, start to water change about 30%. 
  • Then add ¼ teaspoon of rock salt.
  • Do not feed your guppy.

Day 2:

  • Monitor your sick guppy if he/she is still active and has no sign of stress.
  • Feed your guppy with a little amount of live food that they consume immediately. (It’s recommended that you give them baby brine shrimp). Feed the guppy during the morning and afternoon.
  • Siphon the poop of your guppy. The water will remove now about 10-20 percent.
  • Add a stock/old water.

Day 3:

  • Check the red spot on guppy if it is any changes.
  • Add Melafix by API or Methelyn Blue (Check the instruction label).
  • Continue feeding of live food (Baby brine shrimp from morning to afternoon).

Other Option

  • Remove the poop during the water change. (20%-30% water change).
  • Add a small amount of rock salt (one sprinkle only). Do this If you don’t have Melafix or Methelyn Blue.

Day 4:

  • Do not water if you apply Melafix or Methelyn Blue.
  • Continue Feeding of live food. (Baby brine shrimp from morning to afternoon).

Other Option

  • Remove the poop of the guppy (20%-30% water change).
  • Do not add rock salt.

Day 5:

  • Add Melafix. Read the label instruction. or add 1 drop liquid of Methelyn Blue.
  • Continue Feeding of live food. (Baby brine shrimp from morning to afternoon).

Other Option

  • Remove the poop of the guppy (20%-30% water change).
  • Add a small amount of rock salt. (one sprinkle)

Day 6 & 7:

  • Monitor your guppy and check the red spot on guppy if already fade or gone.
  • If still have a red spot, continue the treatment using Melafix every other day to avoid the overdose of the guppies or 1 drop of Methelyn Blue.
  • Continue the feeding method. Morning and afternoon using baby brine shrimp.

Final Day

  • If the red spot has already gone, you treated your guppy successfully and you can now join them in your community tank.



  • Make sure to clean your tank often and remember, that “prevention is better than cure“, especially for the red spot on guppy. Clean your tank every twice weekly for about 20%-30% and remove the poop and excess fish food that causes the high ammonia level in your tank.
  • Add additional filter media that helps to develop beneficial bacteria for our guppies and the ammonia will convert to good bacteria. 
  • Another solution is to add a snail such as an apple snail or ramshorn snail that cleans or eats the excess fish food and poop to your tank.
  • Do not overfeed your guppies and maintain the small amount of food especially the fish food pellet that has a high ammonia effect on our tank if our fish did not consume it immediately.
  • Use the heater to make warm the water. Coldwater will develop fast the bacteria that may cause the red spot.

Final Thoughts

These methods for the red spot on guppy that I share with you are already effective to cure my guppies. All in all, the good quality of the water will prevent your guppies to have sick and do not forget the rock salt for them. The rock salt helps to slime the body of the guppies and avoid the bacteria stick to their bodies. It is also less the stress of our guppies if you put a little amount of rock salt every time you water change your tank.


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