A lot of people like to feed young goldfish and minnows to their oscars.
Feeder fish is a tough topic in our hobby. In my experience, how people feel about it depends on how “sentimental” a person is about fish. And I’m very sentimental. I love fish, and the idea of feeding one fish to another fish just makes me uncomfortable.
Although, it’s strange, while I prefer not to use feeder fish under any circumstances because of said sentimentality, I nevertheless don’t really judge people who do use feeder fish. It’s extremely easy for me to understand that every single person on this planet has their own unique perspective and set of opinions based on that.
However, that’s not to say that—as objectively speaking as possible—I think that feeder fish are a good idea. Because, nine out of ten times they’re a terrible idea!
Let’s start with the most obvious reason: disease. Feeder fish from big box stores are often the sickest fish in the store.
They’re raised on outdoor farms (like most mass produced ornamental fish) and as such they almost certainly come with a host of parasites. But, that’s not the only thing—fish carry diseases the same way we do or any life form does. Those diseases require a weakened host before the illness can overwhelm the host’s immune system. Diseases can reproduce in larger numbers in a weakened host and subsequently affect more individuals.
Keep in mind, feeder fish are poorly treated, therefore, they are prone to being overwhelmed by infectious illness.
The next concern is that, while I admit it’s unlikely, a live fish can become lodged in the mouth or throat or digestive tract of a fish that eats it.
And get this! Some fish are shaped in such a way that they will get stuck in the throat as a defense mechanism.
Catfish are a great example of this, because most of them have spines in their fins that, when threatened, they erect to stick into their enemy. Lots of oscars have died as a result of trying to swallow a catfish whole—especially plecos.
So, for that reason, I don’t recommend encouraging your oscars to prey on live fish because one day they might eat the wrong one.
Bad Habits Die Hard And Nutrition
And speaking of habits, you don’t want to encourage your oscar to prefer feeder fish. Sometimes fish, especially wild caught fish, will be reluctant to take commercial fish foods. It’s much better to have your oscar used to eating a food you have readily available, like a high quality pellet.
This is because feeder goldfish and feeder minnows are not particularly nutritious for your oscar. Whereas, modern commercial fish food is very good (if you buy the right stuff). Personally, I prefer brands like Hikari and Sera, but they aren’t the only good ones out there. I’m also a fan of Fluval’s bug bites, especially for oscars.
In fact, I have a whole article covering some of my favorite fish foods—check it out here.
But, Oscars Eat Fish In The Wild! (Do They?)
Sure, some fish are habitual piscivores (fish eaters), but this might surprise you: oscars are not. Sure, in the wild just about any fish will eat another if it fits in its mouth—they’re all opportunists like that. Oscars included, they will eat fish in the wild just like they will in captivity. But, they are NOT specialized piscivores in the way that a frontosa is for example.
According to Live Aquarium, an oscar’s diet mainly consists of insects and crustaceans. In the wild, fish represent only a small portion of the oscar’s diet.
Also, oscars like to feed off the surface, so as you can imagine they take a lot of insects that land on the water. However, oscars are by no means strict carnivores. They will also eat fruits and berries that have fallen into the water. This taste for fruit is important to keep in mind, because it means oscars need vitamin C in their diet. Therefore, if your oscar gets hooked on feeder fish, it won’t be getting the necessary dose of vitamin C.
You Said “Unless” – So When Is It Okay To Give Oscars Feeder Fish?
Well, there are some circumstances where I think feeder fish might be an okay treat on an occasional basis. But, you have to be super careful to be absolutely, positively sure that your feeder fish aren’t going to transmit parasites or diseases.
So, how can you guarantee that? Answer: by breeding your own feeder fish.
Personally, because of my sentimental nature, I would never breed fish just to feed to another fish. However, when breeding fish, you’ll often encounter deformed fish; these should be culled if their quality of life will suffer due to the deformity. Therefore, if you breed a fish just because you like that fish and you want more of them, then in that situation I’d say you could feed the culls to your oscar.
So What The Heck Should I Feed My Oscar?
You should feed a quality commercial food. Modern fish food manufacturers are fighting to provide the best food. Thanks to the Internet, aquarium hobbyists are better informed than ever. We all know exactly what our fish need, so we all read the ingredient lists and the guaranteed minimum protein, etc.
So, with that in mind, here are some foods that I can heartily recommend for oscars.
Hikari Cichlid Gold
Even the packaging has an oscar on it!
I like this food because it has stabilized vitamin C – exactly what your oscar needs! Hikari Cichlid Gold is a great food, I’ve been using it for years, and will continue to use it with great results. Definitely a much better food for your oscar than feeder goldfish could ever be.
Grab it here on Amazon (affiliate link)
Fluval Bug Bites
Fluval Bug Bites are fantastic. I love them.
They’re made from black soldier fly larvae. So, if you remember earlier on in the article how an oscar’s natural diet is a large part insects? Well, bingo! Bug Bites are insects! They’re a great food for your oscar. I wouldn’t feed them as a main food though, I’d feed some Bug Bites along with some of Hikari’s Cichlid Gold.
Frozen foods are a great option too–you can get chunky, meaty food like frozen shell fish. Or, you can go with aquarium hobby favorites like frozen bloodworm or frozen brine shrimp. You’ve got lots of options to treat your oscar with.