I have three all confirmed male garters in one aquarium. They also are small and slender like males tend to be and basically all full grown except a younger male one that only has a little more growing to go. They were confirmed to be male by the people I purchased them from.

I have had this issue on and off with one adult garter. From time to time, he just stops eating, and literally keeps trying to court the smallest male, and other times court the other equally sized male. I was concerned, and thought the smaller male may be a female(I know the other larger male is 100% male, he use to be a breeder before he was given to me). So..I instead placed the smaller male that the larger male keeps trying to court with a female younger than him yet she is still equal size as him. The smaller male then tried to court her! She was very stressed about it, tail wiggling and everything so I removed him from her enclosure.

So pretty much it's obvious that the smaller male HAS to be a male. I put him back in the main aquarium and gave the sex hungry male a time out for a day. He chilled out and was then willing to eat.

Any way, I digress. I know some times males emit pheromones when they emerge. Is this a case of this? He isn't always trying to mate, and the other males, despite his behavior, don't seem to care. They still want to eat, they still bask under the heat lamp, they kind of just lay there while he's going crazy courting them. Again, it's an on and off thing. Sometimes he wants to court them, for a few days, and then for several days to weeks he shows no interest. Should I be concerned? Should I put the sex hungry male in his own aquarium? Is it possible he is picking up from the pheromones from the female in the aquarium next to him?