Since I recently started back into the hobby, and went with some German Blue Rams, I've been trying to get a better handle on how to tell males from females.
Looking around online, there are all kinds of discussion posts and videos on how to sex rams. But I've found there's also a lot of misinformation out there. Most of the misinformation takes the form of "this is the definitive way to tell them apart" comments. For the most part, they are all wrong about single indicators being 'definitive' markers for male or females. Instead, what I've found to be the case is that there are a number of good indicators of sex, and you really have to determine what some of these stronger indicators are, and take a number of them into consideration.
So I thought I'd make this thread to make it a bit clearer for someone else looking to get an understanding of this. I'm going to make a list of indicators, with some notes beside each, so people can put the strength of the indicator into context. Please feel free to add your own comments below, with pictures if you can, and I'll be happy to edit/update/correct this first post.
Rams experts/owners, let's discuss!
Body shape (strong indicator, but easier to see when visually comparing side by side)
Once you can compare males & females, you'll see there is a definite difference in the general body shape. Looking at the profile of a male, you can see it has a taller, rounder (more squat) body shape. It also has a more extreme curve to it's head/forehead profile line, and a bit of a 'lump'. The female body shape is longer & leaner, with less roundedness to it's over all profile, and head profile that has a more gradual curve.
Longer dorsal rays (strong indicator)
The first few rays on the male's dorsal fin will be longer than the rest of the dorsal fin. The color of the rays is not a definitive difference however. Both males & females can have those first few dorsal rays fins appear black.
Black strips & other black markings (Not an direct indicator at all)
The black markings on the rams (both male & female) are actually more a dominance ranking, and can't be used to directly sex rams. However, it follows that in most cases the rams with the most bold black markings will be a dominant male ram.
Black patch on side - blue speckles showing or not showing over the black patch (Weaker indicator)
Some people will claim that the bold distinctive black patch on the side of a ram can used to sex a ram. This is only true in one case, to a degree - to identify the most dominant male ram, which as logic dictates will be a male. The fact is, and I've observed this personally, even the dominant male rams, if stressed, can have his black patch fade slightly, allowing the blue speckles to show. So blue speckles showing over the black patch is not a definitive indicator of sex. At best, it's a situational indicator that one particular fish is the most dominant and therefore a male.
Red belly (Strong indicator when present)
A red/pink belly showing is a definitive indicator that the fish is a female. However, the absence of a red/pink belly is not an indicator of sex. Either male or female can lack a red/pink belly, but only females will have them. Based on reading & research I've done to date, the red/pink belly may only be present on a female ram under specific conditions; though I haven't had enough personal experience with observing this in order to confirm it personally.
Here's a few pictures of my German Blue Rams. Please feel free to post your own pictures & comments. Please excuse the floaty food bits... it's the best way to get them all together for family picture time.
Here's a picture of one of my new females. Note the red/pink belly and the first few dorsal fin rays that are not taller than the dorsal fin. This is a younger female.
Here's a group shot with the exact same female and my older males. Their relative size in the picture is due to age differences - not gender. Note the differences in body shape. Both of the larger rams are males, and you can see the dominance reflected in the strength of the black marks between the two males. During feeding time colors become much stronger for all of them, and during times of stress they will all lose color. But the less dominant fish will lose their color faster and more often.
Looking around online, there are all kinds of discussion posts and videos on how to sex rams. But I've found there's also a lot of misinformation out there. Most of the misinformation takes the form of "this is the definitive way to tell them apart" comments. For the most part, they are all wrong about single indicators being 'definitive' markers for male or females. Instead, what I've found to be the case is that there are a number of good indicators of sex, and you really have to determine what some of these stronger indicators are, and take a number of them into consideration.
So I thought I'd make this thread to make it a bit clearer for someone else looking to get an understanding of this. I'm going to make a list of indicators, with some notes beside each, so people can put the strength of the indicator into context. Please feel free to add your own comments below, with pictures if you can, and I'll be happy to edit/update/correct this first post.
Rams experts/owners, let's discuss!
Body shape (strong indicator, but easier to see when visually comparing side by side)
Once you can compare males & females, you'll see there is a definite difference in the general body shape. Looking at the profile of a male, you can see it has a taller, rounder (more squat) body shape. It also has a more extreme curve to it's head/forehead profile line, and a bit of a 'lump'. The female body shape is longer & leaner, with less roundedness to it's over all profile, and head profile that has a more gradual curve.
Longer dorsal rays (strong indicator)
The first few rays on the male's dorsal fin will be longer than the rest of the dorsal fin. The color of the rays is not a definitive difference however. Both males & females can have those first few dorsal rays fins appear black.
Black strips & other black markings (Not an direct indicator at all)
The black markings on the rams (both male & female) are actually more a dominance ranking, and can't be used to directly sex rams. However, it follows that in most cases the rams with the most bold black markings will be a dominant male ram.
Black patch on side - blue speckles showing or not showing over the black patch (Weaker indicator)
Some people will claim that the bold distinctive black patch on the side of a ram can used to sex a ram. This is only true in one case, to a degree - to identify the most dominant male ram, which as logic dictates will be a male. The fact is, and I've observed this personally, even the dominant male rams, if stressed, can have his black patch fade slightly, allowing the blue speckles to show. So blue speckles showing over the black patch is not a definitive indicator of sex. At best, it's a situational indicator that one particular fish is the most dominant and therefore a male.
Red belly (Strong indicator when present)
A red/pink belly showing is a definitive indicator that the fish is a female. However, the absence of a red/pink belly is not an indicator of sex. Either male or female can lack a red/pink belly, but only females will have them. Based on reading & research I've done to date, the red/pink belly may only be present on a female ram under specific conditions; though I haven't had enough personal experience with observing this in order to confirm it personally.
Here's a few pictures of my German Blue Rams. Please feel free to post your own pictures & comments. Please excuse the floaty food bits... it's the best way to get them all together for family picture time.
Here's a picture of one of my new females. Note the red/pink belly and the first few dorsal fin rays that are not taller than the dorsal fin. This is a younger female.
Here's a group shot with the exact same female and my older males. Their relative size in the picture is due to age differences - not gender. Note the differences in body shape. Both of the larger rams are males, and you can see the dominance reflected in the strength of the black marks between the two males. During feeding time colors become much stronger for all of them, and during times of stress they will all lose color. But the less dominant fish will lose their color faster and more often.
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