Sexing Sewellia hillstream loaches

[V1K]

I have 5 Sewellia lineolata and 1 S. SE01, I was wondering if anyone has a good eye for sexing them. 1-3 are with me for 3 months. 4-5 I only got a week ago, but the guy at a shop told it's the same batch as my previous ones, although these 2 are much smaller. 6 is the Sewellia SE01, and it also have been in my tank for 3 months (no belly photo as it doesn't like sitting on glass as much as the lineolatas). None of them have so called fences, as far as I can tell.
1. Bai (strong suspicion this is a girl)

2. Hei

3. Sec

4. Cas

5. Din

6. Dax

 

[mimo91088]

Following because I'm still unclear myself!

 

[V1K]

Following because I'm still unclear myself!

Seems like everyone is unclear ...

 

[mimo91088]

I still don't even know what the fences are lol

 

[V1K]

I still don't even know what the fences are lol

I believe you can see them in these photos, on the pectoral fins close to the head, sort of fuzzy bumps. Mine don't have them, but it seems statistically improbable that all 6 are girls, so maybe they're just immature.

 

[mimo91088]

I had similar thoughts as well. I wonder if it's similar to breeding stars on goldfish and they're only present sometimes? I have 7 SW01 and I haven't seen that on any of mine either.

 

[Skrabbitskrabbit]

I found this video that may help
Sexing sewellia

Screenshot (from video) shows the pair she was comparing. Female is bigger, has wider head and body regions, and the shape of the fins more round if I understand correctly
if I had to guess I’d say your girls are 1,2, &4
Boys 3&5 ?? 6?? Who knows. Keyword is guess!
Edit to add : I’ve never seen fences on mine either...

 

[mimo91088]

I'll have to check that video out later!

 

[V1K]

I found this video that may help
Sexing sewellia

Screenshot (from video) shows the pair she was comparing. Female is bigger, has wider head and body regions, and the shape of the fins more round if I understand correctlyView attachment 762465
if I had to guess I’d say your girls are 1,2, &4
Boys 3&5 ?? 6?? Who knows. Keyword is guess!
Edit to add : I’ve never seen fences on mine either...

Yeah, I've seen that video, as well as a few others. All of those seem to use extremely obvious cases, while mine come somewhere in between. None of mine come even close to the appearance of the male in the screenshot, and look much closer to the female. Maybe they all are - unlikely, but not impossible I guess...

 

[Mudminnow]

I'm no expert in this either. But, to me, 1 seems most like a female. 3 seems most like a male. But, after looking at some other online pictures, I am leaning toward thinking your fish may be female. Although unlikely, perhaps you have 5 or 6 females.

 

[Skrabbitskrabbit]

Yeah it does seem like they used the most obviously female/male pairs for the video. I also remember reading that males have a more pronounced coloration. Maybe as they grow, the differences in size, shape, color etc. will become more apparent.

 

[Skrabbitskrabbit]

I got this picture today of 3/4 of mine... #4 is not pictured and is very much smaller than these 3 right now

My guess is that the boy is the one in the middle (with the broken fin).
The bottom (girl?) is the largest of my group (though hard to tell from photo angle) and the top/left fish is the tank boss and alpha (is the alpha typically female??)

 

[mimo91088]

I got this picture today of 3/4 of mine... #4 is not pictured and is very much smaller than these 3 right now
View attachment 768817
My guess is that the boy is the one in the middle (with the broken fin).
The bottom (girl?) is the largest of my group (though hard to tell from photo angle) and the top/left fish is the tank boss and alpha (is the alpha typically female??)

I'm still not confident, but I'd agree with your assessment. As for dominance structure I have no idea. I can't tell mine apart as individuals to even tell IF there's a boss.

V1K Skrabbitskrabbit Do either of your's set up little fighting pits and chase each other in a circle for seemingly forever but never actually attack each other? Mine will literally do this for like 30 minutes sometimes. Trying to figure out if that's a dominance thing or a mating thing.

 

[V1K]

I can't tell mine apart as individuals to even tell IF there's a boss.

I guess it's harder with spotted, as they don't have intricate patterns... Lineolata are like living Rorschach tests, makes it pretty easy

V1K Skrabbitskrabbit Do either of your's set up little fighting pits and chase each other in a circle for seemingly forever but never actually attack each other? Mine will literally do this for like 30 minutes sometimes. Trying to figure out if that's a dominance thing or a mating thing.

They do, but it happens mostly at feeding time, so I think it's competition, not mating. Here's mine fighting after I gave them some peas.

I got this picture today of 3/4 of mine... #4 is not pictured and is very much smaller than these 3 right now
View attachment 768817
My guess is that the boy is the one in the middle (with the broken fin).
The bottom (girl?) is the largest of my group (though hard to tell from photo angle) and the top/left fish is the tank boss and alpha (is the alpha typically female??)

I think top left is male because the head and pectoral fins meet at sharp angle.

 

[mimo91088]

Mine fight like that too, but I'll try to get a video of what im describing. It's like a little full speed whirlwind. They don't stop and try to top each other. It leaves little circle impressions in the sand lol.

 

[Skrabbitskrabbit]

I think top left is male because the head and pectoral fins meet at sharp angle.

honestly it probably is, after watching more YouTube videos it does seem like males are the ones that are territorial so I’m probably wrong
The funny thing is that I bought 2 different pairs from the same seller and the alpha ended up being one of the two new fish (previously it was the broken fin fish).

I'm still not confident, but I'd agree with your assessment. As for dominance structure I have no idea. I can't tell mine apart as individuals to even tell IF there's a boss.

V1K Skrabbitskrabbit Do either of your's set up little fighting pits and chase each other in a circle for seemingly forever but never actually attack each other? Mine will literally do this for like 30 minutes sometimes. Trying to figure out if that's a dominance thing or a mating thing.

Mine have yet to mate that I can tell (only been in my tank since December) but it sounds like it may be mating to me

 

[mrsP]

I have breeding Sewellias in my tank, I bought 6, and now I have something between 20 - 30 of them, all sizes. I would think that nr 1 and 3 are females, 2, 4 and 5 males, nr 6 no idea. However, that's my best guess, not definite. Just keep water extremely clean, but don't clean glass too well to provide them the aufwuch layer to eat, they love that.

 

[V1K]

I have breeding Sewellias in my tank, I bought 6, and now I have something between 20 - 30 of them, all sizes. I would think that nr 1 and 3 are females, 2, 4 and 5 males, nr 6 no idea. However, that's my best guess, not definite. Just keep water extremely clean, but don't clean glass too well to provide them the aufwuch layer to eat, they love that.

I clean front and one side glass regularly for viewing, the other side glass just once in a while when it gets extra gross, and I haven't cleaned the back glass ever. Ironically, they mostly hang out on the clean glass . They graze on all sort of surfaces all over the tank, stones, driftwood, even plants. Not sure if my water counts as extra clean or not - on one hand, its nitrates are always so low I actually add them for plants, on the other hand with barbs around there's always some organic mulm present. However, yours lived with notoriously messy goldfish and were fine, so I guess it's not really a problem?

 

[mrsP]

I clean front and one side glass regularly for viewing, the other side glass just once in a while when it gets extra gross, and I haven't cleaned the back glass ever. Ironically, they mostly hang out on the clean glass . They graze on all sort of surfaces all over the tank, stones, driftwood, even plants. Not sure if my water counts as extra clean or not - on one hand, its nitrates are always so low I actually add them for plants, on the other hand with barbs around there's always some organic mulm present. However, yours lived with notoriously messy goldfish and were fine, so I guess it's not really a problem?

I would imagine it's not a problem, goldfish were REALLY messy, you're absolutely right! I think it's more about water quality, because every natural environment would have some mulm in it.