The clawed mosquitofish is an unusual livebearer that presents somewhat of a challenge to breed and raise. It is best to keep them in a single species tank as they can be somewhat pugnacious, even among themselves. Although it is a gambusia, the body shape reminds me of an Alfaro or knifebelly livebearer with a thin body and deep belly area. The coloration is a delicate blue-gray with some translucency. Cover them well as they are expert jumpers! They usually live and feed at the surface. Soon after they are born, the fry are up at the surface also. Thick hornwort or other floating plants are necessary as they are very cannibalistic toward their own fry. It is difficult to tell when a female will drop her young since she will not get real large. Young females about 1 inch long will drop from 4 to 10 tiny fry at a time. Full sized males will be about 1 inch and females about 1½ inches and they are not very prolific. They do love warmth, and the temperature should not get much below 70 degrees. At 80 degrees they do very well and gestation is about one month. Mine did well in harder water produced by putting dolomite gravel as the substrate. Some references recommend adding some salt but my fish did well without it.
These fish are fast swimmers and probably come from swift moving waters. One reference states that water movement is necessary for their proper care. A hard running sponge filter seemed to provide that for me. Male courtship of the females is very entertaining to watch. The male darts incredibly fast, circling around the female to get her attention or maybe distract her. It is too fast to follow with the eye. I am a fisherman and can only imagine this fish the size of a largemouth bass jumping and whizzing around the boat when hooked! Talk about the ideal gamefish! It would make the steelhead look like a panty-waist!
Gambusia luma eats a variety of foods but especially relishes newly hatched brine shrimp. I like to include dry food with about 50% spirulina flakes to give them some vegetable matter. Daphnia, grindal worms, and frozen brine shrimp were also fed. These fish are sensitive to pollution, so don’t overcrowd them and be sure to make frequent water changes. I would highly recommend this fish as an unusual and somewhat challenging species. It is not your run-of-the-mill livebearer, but an entertaining and active species to enjoy.