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A few questions about these cuties...

I spotted them at Petco and had never seen them before - they're about an inch long, not counting their fins. Any thoughts on how old these little guys might be, and is it possible to determine their sex or type of Betta at this age? Being young, I'm wondering how they'd do in a 20-gallon tank with Mollies to start.

Sidenote... I think I found my new favorite Betta - the Elephant Ear! They're stunning.

Thanks in advance for any info.

I think mollies and bettas might not be the best tankmates. I'm still pretty new to bettas myself, so I don't have a lot of advice to offer. However, I did come across a growth chart that might be helpful for determining the age of those little bettas: http/www.bettatalk.com/fry_growth.htm

Thanks for the info Meadowbloom. I was thinking of the Mollie tank only temporarily. Those little bubs seem to fall into the size category of 6 to 8 weeks - seems kind of young. They were also on the thin side, which caught my attention. I might just have to go back today and take a closer look, maybe even snap some awful photos with my phone. They were just labelled 'Baby Bettas' with no indication of gender or type. I'll do some more research, as I noticed in pictures that their fins at that age already show some signs of development.

Another thing that caught my attention - there were no pellets in the baby Bettas' cups. I'm not sure if they hadn't been fed yet or if they're on a different diet at this age. I'd like to do some research before I go back and ask the staff questions, just to see how they respond. Also, I noticed the adult Bettas had around 8 pellets in their cups, just sitting there - isn't that a bit excessive for them?

I stumbled upon the baby bettas at our local Petco, and I have to admit, I was a bit taken aback that they're putting such young fish through the stress of shipping.

After doing some research, I found that it can be quite a challenge to keep them alive without top-notch care. It seems they require specialized food like baby brine shrimp or fry pellets, and they need to be kept in a warm environment with good filtration. If you're up for the challenge, it could be an interesting experience.

As for determining their gender, I've read that females often have a small white spot on their underside - you might want to take a closer look for that.

Baby bettas are way too young to sex, and their fin shapes are still developing - it's like buying a mystery betta. They're usually too small for pellets and need specialized food, which is why many look so thin in stores. Sadly, a lot of them don't survive because they're so young and people don't know how to care for them. If you decide to get one, a smaller container than what they'd need as adults would be best. A heater and clean water are must-haves, just like with adult bettas. For feeding, I recommend live or fry food - I personally like to give my young bettas frozen baby brine shrimp, decap baby brine shrimp, microworms, and walter worms, which are pretty easy to find depending on where you are. I'm not a fan of keeping bettas with mollies, especially baby bettas - it's just not the best environment for them.

That's really interesting. I'd love to learn more about the age factor in determining gender - at what point can you tell for sure, or is it still a bit of a guessing game?

Thanks so much for all the info - it's been super helpful. I've been thinking about getting a Betta for a while now, but I've had my hands full lately dealing with some tank issues. We just went through the spring water treatment changeover in our city, and it totally threw off my pH levels. One of my Mollies had a huge spawn and it sent my ammonia levels through the roof - what a nightmare. Luckily, both tanks are finally stable again. I'm thinking I'll start making preparations for a Betta soon, though. I love the idea of having a "surprise" Betta and watching it grow from a tiny little thing. I'm still planning on going back to Petco to take a closer look at the babies and see what the staff has to say. Thanks again for all the advice - I really appreciate it. If I get some good pics, I'll definitely post them. And just FYI, the Elephant Ear Betta was $19.99 - seems a bit steep, but it's definitely a beautiful fish.

$19.99 is actually a pretty reasonable price for an elephant ear betta, especially considering my local Petco charges $24.99.

As for determining the sex of a betta, it usually takes around 4 months before it's possible to tell with certainty. Some bettas may be easier to sex sooner, but generally, 3 months or 12 weeks is the earliest that most people, aside from breeders or experienced betta keepers, can accurately determine the sex. Occasionally, you might come across a "baby betta" that's actually old enough to make an educated guess, but that's not always the case. I recall recently purchasing a betta that I estimated to be around 3 months old, and I was able to determine its sex with relative ease, although I couldn't pinpoint the tail type until more recently.

florinka wrote: ↑Tue Apr 22, 2025 4:51 pm A few questions about these cuties...

I spotted them at Petco and had never seen them before - they're about an inch long, not counting their fins. Any thoughts on how old these little guys might be, and is it possible to determine their sex or type of Betta at this age? Being young, I'm wondering how they'd do in a 20-gallon tank with Mollies to start.

Sidenote... I think I found my new favorite Betta - the Elephant Ear! They're stunning.

Thanks in advance for any info.

I'm not sure about the labels, but usually, you can tell by the fins - girls tend to have smaller top fins and shorter tail fins. Guys are the show-offs, often with long tail fins and shorter bottom fins. Researching pictures can give you an idea, but with babies, it's harder to tell. One thing to keep in mind, though, is to use bottled or treated water - they're sensitive to chlorine, and it can be tough on them.