I see this question come up time and time again..most are basicly concerned of either breeding purposes or head hump (since its generally linked to head hump size.) Most would agree that its hard or impossible to tell at sizes below 3/4 inches because their sexual organs arent mature yet for both femal and male..
This is my attempt to shed some light on the issue by listing a few things i have come across in the endless search for sexing your flowerhorn..this should also put away the questions on " will my flowerhorn develop a hump!!"
The list as follows by time line and I am speaking in general so that you can use it as a checklist and the more checks you get the more likely it is one or the other (assuming its not stunt in growth at all):
1) First 8 weeks of fry life- There are no methods to sexing but complete speculation by observing the head size relative to the entire patch..fries that have larger hump are more likely to be male.
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2) 8 weeks to 20weeks of life-
Females are more likely to have a dorsal (back/top fin) marking on fin. (this is not a rule but a again in general/ statistically speaking..it isnt a rule because there are males that can also have this marking but its less likely that it would be a male with a dorsal fin marking.)
Into the later weeks I would say 10+ weeks you can use a method called venting.. while some may have innovative ways of doing it ..i feel that a method where you gentally push/ massage the abdomen so that the gentals pop outward should do the trick..
Males- the thing that sticks out near where they poop/gential papille V shape
Females- the thing that sticks out near where they poop/ gential papille U shape
Males have higher fins both dorsally (on the top/ back of the fish) and caudally (belly/front of the fish) ...reason i said back and front is because for humans beings dorsal is on your back and caudal is in your front its easier to understand this way i feel.
Generally--(this part isnt that helpful) males have more color, are bulkier, and have a more defined jaw shape.
Females (at about 20 weeks will start to lay eyes on flat surfaces and so if that happens and you were still pondering about sex this last fact should let you know without much effort at all..hahah)
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Reasons why sexxing your loved FH has become such a daunting task..
as the hybrid craze is constantly evolving with new mixes of many or pure specimens we are seeing a larger variation of phenotypical fishes that arrive at your lfs or online purchases. Some of these fishes dotn follow the general rules (ex. some females have large humps, some patches that were selected for many pearl and flowerline markings might exhibit dorsal fin marking even as a male sex, some mixes with parrot fish will have bulky bodies depending on strain..etc)
while there are methods of sexing most are observational ..and other then the method of venting all are just educated guesses based on experience however if you do a check list/ or jsut wait and do a venting which is easier and less invasive as it sounds you would save yourself the vague answers you many times get as replies....
I realyl hope this was helpful and for any mistakes or corrections please post a reply. Thank you and all information that was presented here was a result of comments from fellow MFK members and web browsing.. Again i am only human so ill make mistakes too..
Goodluck all hope you get what you are looking for ...
This is my attempt to shed some light on the issue by listing a few things i have come across in the endless search for sexing your flowerhorn..this should also put away the questions on " will my flowerhorn develop a hump!!"
The list as follows by time line and I am speaking in general so that you can use it as a checklist and the more checks you get the more likely it is one or the other (assuming its not stunt in growth at all):
1) First 8 weeks of fry life- There are no methods to sexing but complete speculation by observing the head size relative to the entire patch..fries that have larger hump are more likely to be male.
--------------------------------------------------------------------------
2) 8 weeks to 20weeks of life-
Females are more likely to have a dorsal (back/top fin) marking on fin. (this is not a rule but a again in general/ statistically speaking..it isnt a rule because there are males that can also have this marking but its less likely that it would be a male with a dorsal fin marking.)
Into the later weeks I would say 10+ weeks you can use a method called venting.. while some may have innovative ways of doing it ..i feel that a method where you gentally push/ massage the abdomen so that the gentals pop outward should do the trick..
Males- the thing that sticks out near where they poop/gential papille V shape
Females- the thing that sticks out near where they poop/ gential papille U shape
Males have higher fins both dorsally (on the top/ back of the fish) and caudally (belly/front of the fish) ...reason i said back and front is because for humans beings dorsal is on your back and caudal is in your front its easier to understand this way i feel.
Generally--(this part isnt that helpful) males have more color, are bulkier, and have a more defined jaw shape.
Females (at about 20 weeks will start to lay eyes on flat surfaces and so if that happens and you were still pondering about sex this last fact should let you know without much effort at all..hahah)
-------------------------------------------------------------------------
Reasons why sexxing your loved FH has become such a daunting task..
as the hybrid craze is constantly evolving with new mixes of many or pure specimens we are seeing a larger variation of phenotypical fishes that arrive at your lfs or online purchases. Some of these fishes dotn follow the general rules (ex. some females have large humps, some patches that were selected for many pearl and flowerline markings might exhibit dorsal fin marking even as a male sex, some mixes with parrot fish will have bulky bodies depending on strain..etc)
while there are methods of sexing most are observational ..and other then the method of venting all are just educated guesses based on experience however if you do a check list/ or jsut wait and do a venting which is easier and less invasive as it sounds you would save yourself the vague answers you many times get as replies....
I realyl hope this was helpful and for any mistakes or corrections please post a reply. Thank you and all information that was presented here was a result of comments from fellow MFK members and web browsing.. Again i am only human so ill make mistakes too..
Goodluck all hope you get what you are looking for ...