Kissing gouramis (Helostoma temminckii) are aquarium fish that hail from the southeastern region of Asia -- think Malaysia, Thailand and Indonesia. These family Helostomatidae members also have a handful of other common monikers, such as pink kisser and kisser fish. Physically speaking, telling the sexes apart is not the easiest task.
Kissing gouramis usually grow to anywhere between 10 and 12 inches in length. In nature, these gouramis are green, although captive varieties are sometimes silvery-pink. Out in their native habitats, they're usually seen in sluggish and calm bodies of water chock full of dense plants. Rivers and lakes are their preferences. Kissing gouramis usually are serene and mild in disposition, and therefore need to live in tanks with fish that are alike in that manner. They also need to live with fish that aren't much bigger or smaller than they are. Kissing gouramis aren't usually fussy eaters in captivity and, as omnivores, usually take in anything from brine shrimp to peas and zucchini. Out in the wild, they feed on a lot of zooplankton, water bugs and green algae.
Although male and female specimens are uncannily similar, physical size might be a helpful hint regarding gender. If you get the opportunity to look at a few kissing gouramis together, you might notice that the girls are generally a little larger and thicker-bodied than the boys.
"Kissing" Behavior in Males
Kissing gouramis aren't called that because they're particularly sweet or lovey-dovey. The "kissing" they do isn't actually an indication of love but rather one of a battle. One way you might be able to distinguish between male and female specimens is by paying attention to occurrences of this behavior. Males often fight with other males by rubbing their mouths together -- something that looks a lot like kissing. These guys have notably fleshy lips. This behavior is power-oriented. The "loser" in these situations usually ends the fight by eventually stopping and therefore surrendering. These dominance-driven confrontations are usually innocuous, not perilous.
Determining the genders of kissing gouramis is hard even if you consider size, as the differences in that department aren't necessarily always clear or oblivious. If you're interested in their spawning, you might want to consider bringing a group of them in -- think a minimum of six individuals. That way, they can form breeding "couples" on their own. Soft water is a must for their spawning efforts.