female guppy with a bent back

[ribbones]

just for a bit of context, this fish isn’t mine, and it’s actually my little sister's! parents are divorced, yadda yadda yadda, she’s my half sister, only here 2-3 days a week so i don’t have constant watch over the fish (+ it belongs to her! responsibility being taught, she’s like.. 7.) but i’d just noticed this with her a little while ago, and after some googling and deep-diving with no real answers, i figured i’d come to the people who probably know this stuff best

not exactly sure how old the fish is since she was just a pet store guppy, but she’s turned out to be a pretty hardy one so far because my sister has had her for a few months now. though because of that, i’ve got absolutely zero clue on whether it could just be genetic (heyy scoliosis), a result of the tankwater, or the fish actually being sick. i have almost no knowledge on fish (i’m much more into/knowledgeable about reptiles) but i was preeetty sure that fish spines aren’t supposed to look like that, especially when comparing her to the other guppies she had in the tank. after researching, i was worried that the fish might be sick and might have to be removed and/or euthanized to save the others, but she’s seemed to fare well so far, and none of the others have showed any sort of “signs” of anything...
took a couple of videos + pictures to show just how she looks and how she moves because (again, no expert but just as far as i can see) her swimming doesn’t really seem labored to me? so here those are; i’ve put them into a folder on my google drive.
https://drive.google.com/drive/folders/1Y2qqACN0PJZ4eAJbflt5c_kJvOtQqDD8

if it is sick, my mum + stepdad are unlikely to justify a trip to a vet who'd actually care for a fish, especially since this little lady was just a $2 guppy my sister bought after saving all of her birthday money to get a fish tank. i personally would like to take the initiative to at least give some sort of guess on whether or not her fish is ok, considering the fact that she’s incredibly sensitive with her pets (understandable) and when the last fish died, she was in tears.

i’d just like to know whether to tell her the fish might be sick and to maybe prepare her for it so it won’t hit her as hard, or whether i can tell her that her fish isn’t sick, and just has a “wiggly spine,” just like her big sister does

thank you in advance to any of you who help out here! it’s very much appreciated <3

 

[Colin_T]

Hi and welcome to the forum

The fish is not meant to look like that and definitely has something wrong. Having said that, the fish looks quite healthy besides the bent spine.

There are a couple of reasons guppies get bent backs.

They have a growth in them that puts pressure on the spine and causes it to bend out of shape. Pregnant guppies can develop this to a degree, especially if they are inbred, (and most guppies are).

Internal growths like tumours, cysts or internal bacterial infections (Tuberculosis) can also put pressure on the spine and cause it to bend. There is no cure for tumours, cysts or TB in fish.

Poor genetics can be a factor. If the fish's parents or grand parents had a slight bend in the back, it would be passed down the line to all the offspring. This is made worse if related fish are bred together (brother and sister, mother and son, etc), and this happens a lot in Asia and pet shops all around the world. There's no cure for a bent back caused by poor genetics.

Old age can cause their back to bend a little bit but not normally that much. Bent backs in old fish is usually a combination of soft water, age and being pregnant all the time. The spine gets weaker and gradually bends.

Soft water can cause guppies to bend. Guppies naturally occur in water with a lot of minerals and when they are kept in soft water (has very little mineral content), their bones lose calcium and they can become deformed (bent back).

---------------------------
What is the GH (general hardness), KH (carbonate hardness) and pH of your water supply?
This information can usually be obtained from your water supply company's website or by telephoning them. If they can't help you, take a glass full of tap water to the local pet shop and get them to test it for you. Write the results down (in numbers) when they do the tests. And ask them what the results are in (eg: ppm, dGH, or something else).

The GH is related to soft or hard water. If you have soft water it would be a contributing factor to the bent back. You can add mineral salts like Rift Lake conditioners (designed for African Rift Lake cichlids) to increase the hardness if you need to.

Guppies need a GH above 200ppm and a pH above 7.0.

 

[FishGuest5123]

It could be T.B. Many guppies are beginning to come down with it. If it is there is nothing you can do for it. Is it the only fish in the tank?