Can someone please tell me what sex are my glofish tiger barbs and my purple glofish tetra?

Welcome to the forum

To sex tiger barbs you need to look at the dorsal fin (that's the one on their back); if it's mostly red, the fish is male, if it's only pale red or clear, the fish is female; that should hold true, even though your fish are strangely coloured. In this case, the fish in the top picture is male, the other, female.

Tetras are much harder to sex. You might be able spot the females, if they were full of eggs, as you'd see them looking fatter than the males, especially if viewed from above, but there's no way of sexing that one, from that picture.

I know this is not directly related to your question, but your fish don't look like proper glofish to me, they look dyed This means they've been injected with a dye that will fade in time, but it's a very stressful process for them (many die during it) and it could affect their long term health.

Are these they only fish you have? Both tiger barbs and widow tetras can be very aggressive, and need to be kept in large shoals, if that aggression isn't to become a problem, so that's something you might need to watch out for .

The aquarium guy told me these were genetically engineered with jellyfish genes to glow.... I am concerned now... Either way, these three are together with a couple of swordtail females , and i am planning to get maybe three more tiger barbs later, if i get a bigger tank i have 20 gallon right now. I have noted that the red one chases the yellow one a bit, but they get along most of the time, and the yellow one always gets to outrun him. I am not sure if they are playing or being aggressive....

Your aquarium guy could be right; you certainly can get genetically modified fish; they only glow under UV light, so you can't tell for sure just by looking, as far as I know, it's just that yours look more like dyed ones to me.

Fish don't really 'play'. They do bully each other, test each other out (in case the other fish is strong enough to be a potential mate, or a weakling that needs removing from the shoal) and create social hierarchies, but anything you see that looks like 'play', isn't really.

In this case, as it's tiger barbs, it will definitely be aggression. The more dominant fish is very likely to kill the more submissive one, if you only have a pair, and it might not take long

how many more females or male tiger barbs do you suggest I add to stop the aggression, or how can i make it better for them?

Tiger barbs and black widow tetras (aka black skirt tetras) naturally occur in groups of hundreds to thousands so the minimum number in an aquarium is 10 of each species.

If you want a more peaceful barb that looks similar to the tiger barb you could get ruby barbs (formerly Puntius but now Pethia nigrofasciata) instead. But they don't do that well when mixed with tiger barbs so you would have to choose between them. All barbs and tetras need to be kept in large groups of their own kind.

Having lots of plants in the aquarium can provide cover and protection for the fish if they are being harassed. If you don't have a light on the tank you can use plastic plants instead of live plants. However, if you do have a light you can try Ambulia, Hyrophila polysperma & ruba, Ludwigia, narrow Vallis, Amazon swordplants, and Water Sprite (Ceratoperis thalictroides).

Those plants all do well under average light and without fertilisers. However, if you want to add a plant fertiliser, just get a basic liquid iron fertiliser like Sera Florena, or an iron based tablet you push into the gravel under a plant (Sera Florenette), or some small red clay balls that can also go under the gravel by the plant roots..

----------------------
The painted widow tetra is not a genetically modified fish. There is a company that did add jellyfish genes to a species of danio and it glowed in the dark (see link below for Glofish). However, they are expensive. The painted widow tetra you have is pink because someone either injected it with colour or painted it with paint, usually the later because it is cheaper.
https://shop.glofish.com/collections/glofish-tetra

An easy way to tell if your fish are genetically modified with jellyfish genes is to turn the lights out. The GM fish will glow in the dark. Painted or injected fish do not glow.

fish<3102 said:

The aquarium guy told me these were genetically engineered with jellyfish genes to glow.... I am concerned now... Either way, these three are together with a couple of swordtail females , and i am planning to get maybe three more tiger barbs later, if i get a bigger tank i have 20 gallon right now. I have noted that the red one chases the yellow one a bit, but they get along most of the time, and the yellow one always gets to outrun him. I am not sure if they are playing or being aggressive....

Click to expand...

fish<3102 said:

The aquarium guy told me these were genetically engineered with jellyfish genes to glow.

Click to expand...

This could not be further from the truth and is used as a selling ploy or just the plain ignorance of the employee. I have lost count on how many PETSMART employees I have caught trying to say this type of thing. Fluorescent fish are very common in nature. In fact, a recent study conducted by the American Museum of Natural History found more than 180 species of fish that are naturally fluorescent under blue light. Fluorescent fish can be observed expressing vibrant green, red, and orange fluorescence patterns across a very diverse range of species, including more than 50 families. Parrots, butterflies, spiders, coral and even some flowers glow under black lights.

Glofish "ARE NOT" genetically engineered with jelly fish or any other type of cross engineering, died, painted or injected with any type of florescent. They are simply born brilliant just like the sign says. The color in GloFish is produced by an inherited fluorescent protein gene that is passed from generation to generation and creates the beautiful fluorescence that can be seen when looking at the fish. The fluorescent protein genes are derived from naturally occurring genes found in marine organisms. GloFish are traditionally bred. Their unique color is a hereditary trait that is passed on, just like any other genetic trait.

Next time you overhear aquarium employees try to say that there is some type mad science behind them you can educate them instead.

As far as their sex it is very hard to distinguish the barbs even with looking at the dorsal fin. You can tell the sex of your Glofish with a few physical traits associated with each gender. Females tend to be larger than male Glofish and are more round in appearance. Males are more petite and slender in width. Under the luminance of natural or florescent lighting look at the secondary sripe of your fish, if the Glofish has golden stripes, the sex is a male. If the secondary line is silver, the sex is a female.

You should visit the Glofish website to learn more about each fish you have and you can always call their hotline if you have any questions. I have called many times and they are very always very helpful.

glofishymommy said:

Glofish "ARE NOT" genetically engineered with jelly fish or any other type of cross engineering, died, painted or injected with any type of florescent. They are simply born brilliant just like the sign says. The color in GloFish is produced by an inherited fluorescent protein gene that is passed from generation to generation and creates the beautiful fluorescence that can be seen when looking at the fish. The fluorescent protein genes are derived from naturally occurring genes found in marine organisms. GloFish are traditionally bred. Their unique color is a hereditary trait that is passed on, just like any other genetic trait.

Click to expand...

Hi Glofishymommy and welcome to the forum

The original Glofish were made by injecting a gene from a jellyfish into the developing embryos. I'm pretty sure the first fish they did it to were Zebra Danios. It was done over 10 years ago and was in numerous scientific journals, magazines and even science based television shows and the news. Once the gene is in the fish it remains there and when those fish breed, they pass the genetic trait (glowing) onto their offspring.

Colin_T said:

Hi Glofishymommy and welcome to the forum

The original Glofish were made by injecting a gene from a jellyfish into the developing embryos. I'm pretty sure the first fish they did it to were Zebra Danios. It was done over 10 years ago and was in numerous scientific journals, magazines and even science based television shows and the news. Once the gene is in the fish it remains there and when those fish breed, they pass the genetic trait (glowing) onto their offspring.

Click to expand...

Thank you for the welcome

I posted above on the difference between the original experimental fish of Dr. Gong and what we know as Glofish. It is closer to 20 years now that Glofish came out to the public and the original was created in the late 90's. Wow, I can't get over how time really flies by.

A short answer...
Dr. Gong is given the credit of creating a zebrafish that would only floresce in the presence of toxins with a jellyfish gene but it was his later work using the genes from corals that created a continuous fluorescent of red and yellow that became the Glofish we know. I included an excerpt from the patent of York Tech.

Im sorry I keep editing but I wanted to add that Purdue University did an extensive study that found even if released into the wild the fluorescent gene does not stay in the population. Glofish cannot survive if released in North American waters and that traditional zebrafish consistently beat out their glowing counterparts when it came to winning mates. There also is no evidence indicating the fluorescent genes from GloFish are transferred to any other species.

I read somewhere that California does not sell them but that is also wrong they are late to the party but they do as of 2015.

fish<3102 said:

View attachment 87537 View attachment 87538 View attachment 87539

Click to expand...

I am sorry we got so off track for your question. I have never tried to breed my glofish and the two times I have seen eggs released the whirlwind of longfins was so intense I still don't know which of them actually released eggs. They were also gobbled up really quickly so if you are planning to breed you are going to need at the very least a breeder box but a separate breeding tank would be your best chance of getting a few live fry, you are also going to have to be very VERY vigilant when spawning occurs.

I have a school of 15 Long-fins so that will take me a bit longer to help out with but I can safely assume that I have both males and females.

I have 4 red (the hardest to sex) tiger barbs swimming around and have been watching them the last few days to help answer your question. We were in luck that one of my barbs "Spot" has an odd extra black spot on it's back, so I was able to use him as the one to compare and was positive I wasn't mistaking it for the same fish. All my barbs are teetering adulthood and around the same size but unless they come up to the glass for feeding they are really quick and super agile swimmers especially when together. The red nose theory did not apply because all their heads are completely red, dorsal fins all black with red stripe so it was up to the shape and color of the anal fin to determine the sex. The shape and black stripe are consistent with all 4. The only difference I could find is that Spot and friend have a red marking just at the tip where the two others do not. If we follow the traditional way to sex barbs this would make Spot and his friend males and the other two female. Looking at your pictures you most likely have 2 females.

I should really have 5 barbs together for their own happiness but these were all my LPS had in stock and they are a very tight little group even without a 5th. They have been together so long and barbs are notorious nippers so I worry adding another would throw off their dynamic and spark aggressive behavior. I do recommend that you if you have a 10 gallon tank you remove the tetra and add 2 or 3 more barbs and do the same in a seperate 10 gallon for the tetra. You will see a big change in their mood and socialization. If you have a 20 gallon tank you can keep them all together, you will be at max capacity, even over a little so water changes and testing has to increase. They are both types of social fish and really belong in schools.