Why is My Pleco Turning White?

Is your pleco turning white?

That’s a very bad sign for the health of your fish. It most often indicates that a pleco is stressed from poor water conditions or improper nutrition. I will cover the exact things you can do in order to get your pleco back in full health.

Improper Nutrition

A common misconception amongst pleco owners is that plecos don’t need to be fed.

This is not actually true. Yes, it’s true that plecos will eat the algae on your tank, but you need to feed them a little more than just algae for them to stay healthy.

Failure to feed plecos a proper diet may result in plecos turning white.

The good news is that plecos eat a lot of different types of food. You can feed plecos carrots, zucchini, cucumbers, and even wood. I recommend feeding them some vegetables a few times a week so they can meet their nutritional needs. There’s also special pleco food designed specifically to meet their nutritional. It’s not entirely necessary to feed them special food, though.

Your Pleco is Stressed

Stress can also cause your pleco to turn white. Fish experience stress for different reasons, so it’s important to know all the reasons to properly diagnose your pleco and reduce the stress. Some of the things that can cause your pleco to become stressed include:

  • Underfeeding.
  • The wrong tank parameters.
  • Tank mates that are too aggressive.
  • Improper tank environment (ie. not enough cover)
  • Living in a small tank

The most common issue is aggressive tank mates or not having enough cover. Plecos really like to have hiding places that don’t get much light. They’re also a relatively docile fish, so they don’t handle tank mates that chase them around the tank well, either.

So, if you don’t have any hiding spaces for your pleco and/or you have other fish in the tank that are aggressive to the plecos, then I recommend fixing those problems. Sometimes all it takes is giving the plecos some hiding spots from aggressive tank mates to remedy the problem.

If that does not work, then you will have to remove the aggressive tank mates from the fish tank.

Your Pleco Has a Disease

Plecos are a fairly hardy fish, but they can still get diseases. These diseases can stress them out and cause them to turn white. The most common diseases for a pleco to get are the following:

  • Fin rot
  • Dropsy

Ich is probably the most common disease for a pleco to get. It’s usually caused by overcrowding in a fish tank. You can spot ich by looking for small white patches on your fish. It’s a fairly easy disease to treat if you catch it early. Just drop some anti-ich treatment in the tank for a few days and it should go away. Make sure to remove any snails or shellfish from the tank because the ich treatment will kill shellfish.

The Water Parameters are Off

As mentioned earlier, plecos are a fairly hardy fish and can survive in a variety of water conditions. However, the ideal water conditions are a water temperature from 75F to 80F and a pH of 7.2 to 8.

If the water parameters are outside those, then it may stress your pleco out and cause them to turn white. I recommend testing your water if your pleco is white and fixing the water parameters if they are not in the recommended range.

Your Tank is Too Small

Plecos start out small, but they can get quite large with some species growing to as large as 30 inches.

That’s a big fish.

This means you need a fairly big tank to prevent them from getting stressed out. I recommend you have a 75 gallon tank at an absolute minimum if you have plecos. The bigger the tank the better, though. Some aquarium enthusiasts recommend a tank as large as 150 gallons for plecos.

You definitely don’t want to put plecos in a 10 or 20 gallon tank. The problem is that as the pleco gets bigger it will start to outgrow the tank. This will stress it out and stunt its growth, which can cause it to turn white.

Final Thoughts

That covers it for all the reasons that your pleco may be turning white. It’s almost always caused by stress or improper nutrition. I recommend first ensuring that your fish tank has the proper water parameters for plecos (water temperature from 74 to 80 and a pH of 7 to 8). And then making sure that you have plenty of hiding spaces for your pleco in the tank.

Leave a Comment