Oscar Isn't That Grouchy - Lemon Longfins
Pfauenaugenbuntbarsch is the German name for the Oscar; a fish famous for its good looks, hardiness and most of all, its “personality” and intelligence. We love this name. Over decades of aquaculture, a variety of morphs of this fish have been bred into existence like Albino, Ruby, Copper, Blue, Orange and Tiger Oscars, sometimes with long flowing fins too. Recently, a new variant of the Oscar has become available: the Lemon Longfin Oscar. We have to think that the German name for this fish is likely Zitronenpfauenaugenbuntbarsch, or literally translated, the Lemon Peacock Eye Cichlid. If you haven't fallen asleep yet, you're our kind of people. We're great at parties. The scientific name for this fish has a history of weirdness that we're not going to get into, just know it is called Astronotus ocellatus.
Lemon Longfin Oscars can get fairly large and small ones grow like crazy at first. They reach maturity (the ability to reproduce) somewhere between six and ten inches long, and they'll easily hit this length in just over a year if well fed. Once they start spawning, their growth slows dramatically. We've known some Oscars to live more than 15 years, and even though they hit 12 inches in the first year and a half, they only ever got 14(ish) inches long. 12-14 inches is still a big fish and this size (and the fact that they are allegedly delicious) means they're a highly sought after food fish in their native range in South America. There is another well-established population of them in South Florida Canals, as a result of a deliberate stocking event in the 1950s (according to www.floridamuseum.ufl.edu). Oscars are regularly harvested out of these canals for food, and just as often are targeted for sportfishing. (Side note, the world record for hook and line fishing is 14.1 inches, and the weight record is 3lbs 8oz!)
Long story short, this is a pretty big aquarium fish. When you get your Lemon Longfin Oscar, they're likely to be only a couple inches long, but as we've stated, this won't last for long. The Longfin variants generally don't get quite as big as the wild fish, but you should still plan for a fish that will be eight to ten inches long at maturity. You will need a pretty big aquarium to keep these, and they do great in ponds for those of you who live in tropical places or can bring them inside for the winter. We suggest having a a tank that is least 125 gallons for a pair of them, and more would obviously be better. These are extraordinarily messy eaters and the filter system you choose should reflect this; aim for ten times the tank volume per hour (or more) in filtration. The fish don't need, or necessarily want current, but you want the most aggressive filtration you can get without the current being overwhelming. The display should feature lots of cover in the way of driftwood, large rocks and maybe floating plants. Oscars are famous for their penchant for digging and moving stuff around, and so substrate rooted plants usually don't last very long. Plants that can grow out of the tank could be grown if the roots are protected. A substrate is not required, and many if not most Oscar keepers don't use any, to help keep the aquarium clean.
Water quality wise, even wild Oscars aren't overly picky, and the Lemon Longfins are the product of selective breeding for thousands of generations. They'll be fine in your aquarium unless your pH or hardness situation is extreme. The one parameter that Astronotus ocellatus is susceptible to is temperature. 55 degrees Fahrenheit is lethal for them. For happy fish, we recommend keeping your aquarium in the 72–78-degree range. Luckily, they are also very durable fish, and so even though they make a big mess when eating, they are also fairly tolerant of higher-than-average nutrient loads. We never recommend having nitrates get over 20ppm in pretty much any display, but we've seen Oscar displays nearly double this for long periods without any apparent effect on the health of the fish.
The best Lemon Longfin Oscar display is one that features them prominently. Either as a pair, or a small group. They can be kept with other fish, and at the very least a pleco can help you keep the tank clean. Some aquarists also stock some smaller fish like Danio's with the Oscars to help eat the uneaten bits of food but be still fast enough to not turn into food themselves. Other south American Cichlids are frequently seen in Oscar displays; fish like Jack Dempseys, Fire Mouths, and convicts all make good choices, and are good contrasting colors for the Lemon Longfins. Stay away from notorious fin nippers like Tiger Barbs as the flowy fins of the Lemons is just too tempting and will get chewed on.
Lemon Longfin Oscars will eat just about anything and have been getting fed a pelletized food since they were old enough to eat them. In house we give them the Nutramar Freshwater Complete Pellets, and there are two sizes of these for when the Oscars get bigger. Feeding them a diet that is primarily quality pellets offers them a protein dense, nutritionally complete meal that is much less messy than live food, which helps keep your tank clean. They'll also relish the opportunity to eat live foods like worms, grubs, small slow fish etc. These messier foods should be fed sparingly, or as treats for your fish to eat, and you to watch!
Pretty much everyone loves Oscars. They learn to identify people quickly and will react to their aquarists coming up to the aquarium, many look for pets and scratches from their handlers too. If you ask anyone who has kept one about keeping Oscars, they'll all bring up two things, that first year of growth, and their huge whack of personality. In captivity, Oscars have been known to live for a decade or more, so be prepared for a long-term commitment. If you're ready and have that big tank waiting for something amazing to live in it, Lemon Longfin Oscars have our highest recommendation. Ask your LFS about getting you a couple from Aquatropic today!