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How To Treat A Guppy With A Split Tail!

Guppies are available in many different types and they have beautiful and flowing tails in most varieties–even in the common guppies.

The fancy guppy and the fan tail guppy have magnificent tails in the males that can easily get hurt on items in the fish tank or by another fish.

The guppy tail can have splits in it from an injury and if it’s not noticed and treated right away, bacteria can form, and then it leads to tail rot.

Guppies also need the right type of fish food to remain healthy and, of course, the correct water parameters to remove bacteria from the tank.

Bacteria forms in your aquarium from the fish waste and any uneaten food that falls to the bottom in the substrate and then it spoils to turn into bacteria.

Water changes should be done more often for a split tail guppy and a full water change, followed by partial water changes more often than usual.

You should also monitor the water conditions daily and add medication to the water. Also, take note of the attitudes of the fish to discover if a fish of a different species or another guppy is being aggressive to the hurt one.

Why Is My Guppy’s Tail Split in Half?

Many different things can cause your guppy’s tail to split in half or in several places. Since they have long and flowing tails, they may have scratched them on some form of decoration in your aquarium.

It’s best to make certain there are no pointed edges on the decorations each time you do a full water change and scrub the items by running your fingers over them.

Water flowing on a decorative piece for a long period of time can actually change it and make it more rough or sharp, just as water in a stream that is flowing can eventually cut through rocks in the bottom.

A guppy can have a split tail from another aggressive fish that was fighting with it or it can occur if a male fish is too rough when trying to breed with a female fish as well.

This happens most often when the male is older and much larger than the female fish. Good tank mates for guppies include platyfish, molly fish, swordtail fish, and the discus fish to be docile and friendly to your guppies and they will also add variety and color to your aquarium.

Furthermore, a tail can split on a guppy if the water conditions are not in the optimal parameters or if they are eating a diet that is subpar and doesn’t provide them with enough vitamin D.

Vitamin D helps fish to grow properly and increase their muscles as well as helps them to have healthy fins and tails.

How To Treat A Guppy With A Split Tail!

The first item to note is that you don’t need to remove the fish with the damaged tail and put it in a quarantine tank, because split tail is not contagious to its other tank mates.

You should start with a complete water change and make certain that you clean your decorations in the tank with a brush and rinse the substrate at the bottom of the aquarium thoroughly to remove any bacteria in the tank.

After you do the complete water change and clean the tank and all its items thoroughly, refill the water and bring it up to the correct parameters for guppies of between 6.8 to 7.8 for the pH, a water hardness or GH of 8 to 12, and a water temperature of 50 to 85 degrees F.

You can add antibiotics to the aquarium, such as erythromycin and aquarium salt to help the water quality and begin healing your fish.

If you aren’t sure why the tail is split on your guppy or the procedure to heal him, you can schedule a video call with a veterinarian for a nominal fee to discuss it with him. The vet will give you a diagnosis and a treatment strategy as well.

Will A Split Guppy Tail Heal By Itself?

Most of the time, instead of the tail repairing itself, it will continue to get worse and he will develop fin and tail rot, which is characterized by parts of the tail falling, being discolored on the tail, or clotted blood on the ends of the tail, as well as a lack of appetite.

When bacteria in the tank is on the split part of the tail, it turns into tail rot. A guppy cannot usually survive tail rot, so it’s best to treat the tank right away before its split tail gets to this point.

You should also check your fish food and make certain it has enough vitamin D in it, such as TetraMin tropical flakes with 1,400 IU/kg of Vitamin D-3, which will help to grow the tail back together where it is split.

You can also add live plants to the aquarium to filter out bacteria as well and do a complete water change each week for several weeks while your guppy heals.

If you notice a tank mate that is being aggressive towards the affected fish, you can replace it with a different type or a more calm fish to prevent this from happening again.

If the tail hasn’t ripped any further and your guppy has no new symptoms with new tail regrowth and an increase in appetite, then you know he is healed and you can cease the weekly complete water changes for a split tail guppy.


Guppies are said to be one of the easiest fish to take care of for new aquarium owners–and this is true. But all fish need the correct diet for good growth and a clean and bacteria-free environment in order to thrive well. Keeping up with water changes is a huge part of owning any fish and also providing the correct fish tank mates that are as docile as a guppy can prevent split tail guppy.