I've got a bunch of Geo redhead tapajos fry in a 75g and they are starting to get big and I feel like I need to start removing some. I'm looking to keep mostly females because I've only got one currently who is always being hit on by 5 others. When can you start venting to sex them? They are all about 3" currently. I would use their fins to sex them but I feel like it will be way too crowded before I can confidently sex most of them that way
when can you vent geophagus
- Thread starter jamntoast
- Start date
I can't give you a direct answer, but since no responses, so far, here goes...
I've never bothered to vent mine, which is why I can't advise you when to vent them. Depending how many you have, though, at 3 inches you should start to see some males emerging before long. IME by 3 to 4 inches males are starting to outgrow females, show more color, more male looking fins, as in longer, more pointed fins or fin extensions starting to appear. Really, by 4 inches you pretty much have young adults that may already begin pairing and attempting to spawn. Like a number of cichlids, from a decent sized group, you might get a few of what I call 'stealth males', those that take more time to show male, but I can usually spot these also by 4 inches.
At 3 inches you can still keep quite a few in a 75, plenty enough to assure a mix of males and females until you can visually pick out some males/females or some of them start pairing. If the idea is to sell some at this point and you're wanting to sell them as gender specific, my guess would be that venting may well be possible, maybe with some magnification, since other sexual characteristics are starting or will soon start to become evident.
I've never bothered to vent mine, which is why I can't advise you when to vent them. Depending how many you have, though, at 3 inches you should start to see some males emerging before long. IME by 3 to 4 inches males are starting to outgrow females, show more color, more male looking fins, as in longer, more pointed fins or fin extensions starting to appear. Really, by 4 inches you pretty much have young adults that may already begin pairing and attempting to spawn. Like a number of cichlids, from a decent sized group, you might get a few of what I call 'stealth males', those that take more time to show male, but I can usually spot these also by 4 inches.
At 3 inches you can still keep quite a few in a 75, plenty enough to assure a mix of males and females until you can visually pick out some males/females or some of them start pairing. If the idea is to sell some at this point and you're wanting to sell them as gender specific, my guess would be that venting may well be possible, maybe with some magnification, since other sexual characteristics are starting or will soon start to become evident.
Yea what I'm seeing is pretty much what you are describing. I can tell which ones are males but I cant till which of the others are just slow growers or female. I don't want to sell off my nice males only to end up with some small weak males. I wish they would start pairing off so maybe some behaviors would give them away
So just 2 days after I'm trying to sex these guys guess what, I have a pair that's laid eggs. Definitely the youngest pair I've had, and they are right to business. I think I will try to separate them so they can raise their young themselves, given I don't expect this first clutch to get too far. I actually thought both of these were male because they both have a bit of a point on the caudal fin, now that I can clearly tell which one is female its obvious the males is longer but very interesting. Here's a pic of the happy couple
Juveniles cannot be vent. Only subadults approaching sexual maturity can be vent, but by then, some external sexual characters will show up. So venting is more useful to confirm the gender than to tell the gender in the absence of any external clues. I found it easier to vent if I can compare two fish side by side, with the sex of one known.
