Guppies and Endler's livebearers are two very popular and very closely related freshwater aquarium fish. Although they look similar at a glance, anyone can see they're not quite the same. But what are the differences? If you're looking for a vibrant, active addition to your tank, which of these two super-colorful, beginner-proof species should you go for?
We've kept hundreds of both, so let's take a look at what they have in common, what they don't, and whether guppies or Endlers are better for your tank.
Also known as the rainbowfish or millionfish, the fancy guppy is the aquarium staple. How many of us started out with a few guppies as kids?! They're native to northeast South America (including the Caribbean), but have been kept in aquariums since the second half of the 19th century. The species has also been introduced around the world as a form of mosquito control, as it has a big taste for mosquito larvae. Unfortunately, this has had a negative effect on the native fish population in most areas.
Wild-type guppies are mostly light brown with a few splashes of color, much like Endlers (see below). More than 100 years of selective breeding has produced the fancy guppies we know today, with larger bodies, much longer tails, and lavish patterns that almost look painted on.
Almost every larger city has a guppy breeders' association for you to join, and there are many long-established lines with set colors and patterns. There are even special guppy competitions where your prettiest fish could win a prize!
Endler's livebearers are very closely related to fancy guppies, but most of the ones found in aquarium stores still look much closer to wild fish. They're smaller and carry their color in splashes or blocks, not gradients. Most lack guppies' intricate patterns, though some do have a more guppy-like appearance thanks to hybridization. Their shorter tail fins give them them a much quicker and more active swimming style; these little livebearers are always on the move.
Endlers have only recently started becoming very popular in the aquarium hobby. This might have something to do with their narrower natural range — they're only found in northern Venezuela — but also with their guppy counterparts gradually weakening due to inbreeding. Most Endlers are still strong and hardy, and many aquarists also appreciate their slower reproductive rate.
Despite their soaring popularity, there still aren't as many established Endler lines; most of the ones at your local aquarium store will just be random grab bags. They're still more "niche" and usually folded into guppy associations rather than having their own following.
There are a few differences between the kinds of tanks these livebearers do best in. We've already seen that fancy guppies are larger than Endlers; a trio of Endlers could do okay in a 5-gallon aquarium, but guppies really need at least double that. But long-finned guppies, particularly the dumbo variety, don't do well in very large or tall set-ups. They can't swim as well and can become exhausted or unable to reach the surface to eat, making Endlers the more flexible fish when it comes to tank size and shape.
Both these livebearers appreciate plenty of cover in the form of live plants. They prefer still to slow-flowing waters in the wild, but again it's the fancy guppy that's more particular about it. You should use gentle filtration in long-finned guppies' tanks, or they'll be blown all over the place.
Both wild guppies and Endlers are hardy and tolerant to a wide range of water parameters. They've been found thriving in polluted waters and can even handle a salinity up to full seawater when acclimated gradually. While most Endlers and "mutt"-type guppies with highly mixed genetics are still almost as flexible as their ancestors, the same can't be said for the extremely fancy and long-finned varieties.
Only inbreeding can produce stable guppy lines with beautiful colors and flowy fins. It can also weaken strains over time, however, especially if the breeder just wants to produce as many pretty fish as possible to sell and doesn't bother to introduce fresh genes from time to time. Many long-time aquarists have noticed guppies gradually becoming weaker over time. They can be more prone to disease and "sudden death syndrome" than Endlers, although we have to say you can still get lucky with wonderfully tough strains.
As long as their tank is fully cycled , both Endlers and mutt guppies do well in a wide range of water parameters and temperatures. Most can handle the occasional parameter swing or beginner mistake, though it's still usually the Endlers that win out when it comes to hardiness. They can even be kept without a heater if your home stays toasty year-round! Highly fancy guppy varieties, on the other hand, are more specific about their environment. They do best in slightly alkaline and moderately hard water, and they need absolute stability.
If you'd like to keep your livebearers in a community with larger (medium-sized) fish, you might think guppies are the better choice. True, short-finned mutt guppies probably look like less of a snack than tiny Endlers. But their long-finned counterparts are sitting ducks not just for predators, but also for nippy schooling fish like many tetras. Those flowy tails are just irresistible, and they're too slow to get away when someone bothers them.
Endlers and most guppies can do well alongside a wide range of peaceful community fish. For the super-fancies, however, we'd recommend only the mellowest tankmates. Try dwarf corydoras — or maybe just a few snails if you really don't want to risk it.
What about shrimp? This is The Shrimp Farm, after all. Both guppies and Endlers can be kept with fast-breeding shrimp like Neocaridina , though they will snack on newly hatched babies if they get the chance. Endler's livebearers are the safer option simply because they have smaller mouths; long-finned male guppies also work well because they're slower swimmers. Female guppies, the biggest and quickest of them all, are the riskiest choice with your shrimp colony.
Both guppies and Endlers give birth to live young instead of laying eggs and are very prolific. The males are always looking for females to breed with; despite the females being less colorful, it's best to keep more of them to prevent the boys from pursuing them too relentlessly. You can also consider keeping only males, which additionally helps prevent your tank from becoming overrun. A healthy livebearer female is practically always gravid (pregnant)!
Speaking of overrunning, fancy guppies are known to breed more often and produce bigger clutches than Endlers. On the other hand, they're also more prone to eating their own babies. Unless the tank is densely planted, the survival rate can be low. It's up to you whether that's a problem or not — it's sad, but unless they belong to fancy or very pretty lines, it's pretty difficult to find homes for dozens of baby guppies a year.
In most cases you should just get the fish you like best.
Although both these livebearer species have their quirks, they're among the most popular aquarium fish in the world for a reason. Thanks to their easy care and hardy nature, almost any aquarist can keep them. Although fancy guppies may be a little less flexible than they used to be, that doesn't mean they'll keel over if you look at them wrong.
Still worried about guppies' inbreeding depression? You can avoid a lot of it by steering clear of the extreme long-tailed, über-fancy guppies most likely to be weakened by extreme line breeding. Or if you do prefer them over shorter-finned varieties, be mindful of who you buy from: dedicated, specialist aquarium stores usually source their stock much more carefully than pet store chains.
As for Endlers, you can deal with their less fancy looks by just taking matters into your own hands. Why not read up on how to establish livebearer lines around certain traits you like and challenge yourself to create the prettiest Endlers around? You can even select for the biggest fish every generation if you think they're too small!
If you do have some specific concerns, you should choose Endler's livebearers over guppies if:
You should choose guppies over Endlers if:
Good point! These two livebearer species can and will produce fertile offspring. In fact, when it comes to Endler's livebearers you're pretty much always dealing with hybrid fish unless you specifically hunt down a documented pure line. Breeding Endler's livebearers with guppies can give them more desirable patterns and color combos, which is why almost all the specimens you'll find at your local fish store already carry some guppy blood.
Mixing Endler blood into guppy populations is less common, but it could be a good way to obtain fish less likely to suffer the heartbreaking "sudden death" syndrome or the genetic deformities fancy guppies can develop. Plus, Endlers do tend to sport brighter colors, especially the oranges — first-generation mixes can look beautiful and throw all sorts of fun surprises.
Just please don't ever do this if you have somehow been lucky enough to find non-hybrid Endler guppies. Not that you'd be likely to, as it can take some real work (and money) to obtain true Cumaná, Campona, and other pure Endler strains. But still! They're highly endangered in the wild, so we can't afford to lose the few pure populations left over to genetic mixing.
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Karino, K., Orita, K., & Sato, A. (2006). Long tails affect swimming performance and habitat choice in the male guppy. Zoological science , 23 (3), 255-260.