Mates For Your Mollies 🐠

21 May 2021


The Brown Hoplo (Hoplosternum littorale) is actually a good place to start. It's a member of the Callichthyidae, the same family that contains the Corydoras catfish so popular with aquarists around the world. Compared to Corydoras it is a much bigger (6-8 inches) catfish with a more robust build and boisterous personality. It can be a bit disruptive in community tanks and does tend to uproot delicate plants, but that shouldn't stop it being selected for large (55+ gallon) aquaria alongside any number of other fish species. In the wild it is usually found in swampy habitats including brackish water marshes along the southeastern coast of South America as well as several offshore islands including Trinidad where this catfish is a highly prized food fish. Over short periods at least, it can tolerate surprisingly high salinities, and it actually does rather better in slightly brackish water than the soft, acidic water conditions favoured by Corydoras. Not in the least shy and completely omnivorous, the Brown Hoplo would make a superb companion for large livebearers that need slightly brackish water at a specific gravity of around 1.003, for example Mollies. Click here to buy the Brown Hoplo

Another good companion for Mollies and Brown Hoplos would be the Fat Sleeper (Dormitator maculatus). As noted earlier, this fish has a very wide distribution. It is sometimes found in the sea, but does seem to favour low-salinity streams and marshes. If kept in plain freshwater this species tends to be sensitive to opportunistic infections, a common trait among brackish water fishes, but kept at around SG 1.003 it is extremely hardy. In the wild some adults may be anything up to a couple of feet in length, but most specimens are much smaller, and in aquaria this holds true too, the average adult being about 12 inches in length. While omnivorous their predatory capabilities should not be underrated, and very small tankmates such as Guppies would be viewed as food. But fish too large to swallow whole are ignored, and in fact Fat Sleepers make excellent aquarium fish. Click here to buy the Fat Sleeper

One of the most celebrated gobies in the hobby is the Violet Goby, sometimes called the Dragon Goby. Curiously, at least two species seem to be traded under this name. North American aquarists usually get the Atlantic coastline species, (Gobioides broussonnetii), but European aquarists often get the Pacific coastline species, (Gobioides peruanus) instead. The two species are very similar, but Gobioides peruanus has much weaker violet markings on its flanks compared to the obvious violet chevron-shaped markings that run from the head all along the flanks of Gobioides broussonnetii. In any case, care is identical, and needs to reflect the peculiar environment these fish inhabit. In the wild they are usually found on mudflats and river estuaries where they live in burrows when the tide is out and only emerge when the tide comes in. So a tank with sand for digging and a few hollow tubes they can use for shelter are important. Feeding can be problematic only insofar as these big fish (potentially 18+ inches in length) and need a lot of food. They are actually rather omnivorous and naturally consume algae, plankton, and tiny animals sifted from the sediment. So offer them a mix of algae wafers, live brine shrimp and daphnia, and wet-frozen invertebrates such as krill, bloodworms and glassworms. Neither of the Violet Gobies is fussy about salinity provided there is at least some salt in the water; anything between SG 1.003 and 1.010 will suit them just fine. Click here to buy the Dragon Goby