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How To Take Care Of A Sucker Fish: Pictures, Info, Food, Lighting & More

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By Lindsey Stanton

orange pleco

Without a doubt, suckerfish are some of the coolest fish out there. In our opinion, watching them sucker themselves into hard surfaces and watching them eat food with that cool mouth of theirs is devilishly entertaining. To be clear, for the purposes of this article, we are going to be talking about the Pleco or common Pleco, the most common type of aquarium suckerfish that people have in their homes.

No, Plecos are not the only kind of suckerfish out there, but they are the most common ones to keep in home aquariums. How to take care of a suckerfish, specifically the Pleco, is what we are here to discuss right now.

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Suckerfish Tank Size

bristlenose pleco with plants in aquarium
Image credit: TTONN, Shutterstock

How Big Do Sucker Fish Get?

Don’t be fooled by the small size of the suckerfish or Pleco that you find in pet stores. Those are usually only around 3 inches long, but they can easily grow to 12 inches in length.

There are some suckerfish species, even the Pleco, which can on occasion grow to a whopping 24 inches or 2 feet in length. Therefore, you need to provide them with a large tank so they can live comfortably and happily.

Recommended Tank Size

For the smallest suckerfish out there, the 12 inchers, you want a tank that is 20 gallons in size at the very minimum. Even for the smaller guys, something like 30 gallons is probably best.

However, for the bigger suckerfish, the 2 footers, you will want a 50 or even a 60 gallon tank. Generally speaking, the tank should be at least twice as wide as they are long, and at least 3 times as long as the length of the suckerfish, if not a little bigger.

You don’t want to have a suckerfish like a Pleco in a tank that is too small. If they start to outgrow their tank, they can get really aggressive and start exhibiting weird behavior. At the same time, it will cause the water quality to drop.

The more fish, food, plants, and waste there is in a limited space, the dirtier the water will get in a fairly short amount of time.

How Long Do Sucker Fish Live?

Keep in mind, these guys can live up to 15 years, so you do need to provide them with a good long term home.

sunshine pleco
Image credit: Pavaphon Supanantananont, Shutterstock

Suckerfish Tank Conditions – The Water

Now, in terms of the water itself, while suckerfish like Plecos are fairly hardy and resilient, you do need to meet their needs pretty spot on for them to be as happy and healthy as possible. First and foremost, you need to make sure that the water is at the proper temperature.

These are technically tropical fish, so the water needs to be fairly warm, ideally between 72 and 78 degrees Fahrenheit. This means that you will need to get yourself an aquarium heater and a thermometer so you can always keep track of the temperature. Having the water either too hot or too cold are both bad scenarios that can end in disaster fairly easily.

What is pretty convenient about suckerfish like Plecos is that they can handle varying pH levels in the water, or in other words, how acidic the water is. The pH level for a suckerfish needs to be kept between 6.5 and 7.5 (more on lowering pH level on this article, and increasing pH level on this article).

This means that your suckerfish can handle a low level of acidity or alkalinity (basic). Either way, as long as you don’t tip the scales too far in either direction, all will be fine. In terms of water hardness, they require a dH level between 5 and 19.

Finally, suckerfish do produce quite a bit of waste, so you need to make sure that you have a well-functioning filter. For instance, if you have a 50-gallon tank, you should have a filtration unit that can handle at least 200 gallons of water per hour, or even better, 250 gallons per hour. This will ensure that the entirety of the tank is filtered at least 4 or 5 times per hour.

Moreover, the filter needs to be a 3 stage mechanical, biological, and chemical filtration unit. Don’t forget to perform regular cleaning and water changes either. While suckerfish are quite hardy and resilient, nobody and nothing likes to swim in dirty, smelly, and polluted water, so make sure that you stay on top of filtration and cleaning requirements. You should be changing about 20% of the water every 2 weeks to ensure optimal water quality.

Image Credit By: Petr Kratochvil, pixabay

Suckerfish Substrate, Plants, & Decorations

Now it is time to set the actual tank up. In terms of the substrate, you absolutely need to have aquarium sand in the bottom, at least 2.5 inches of it. You should not be using aquarium gravel unless it is extremely soft, fine, and smooth.

This is because suckerfish like Plecos enjoy being at the bottom of the tank, often sliding their bellies right along the bottom. Therefore, sand is the best option in order to prevent scratching and other injuries. They like to burrow too, so sand is great.

When it comes to plants, unfortunately there are not many options to go with. Suckerfish, especially Plecos, really enjoy uprooting, eating, or just destroying plants. If you do want to have some plants in there with your suckerfish, you need to ensure that they are very well rooted, hardy, and quick growing.

Simply put, most plants just won’t stand a chance with a Pleco around. That being said, some leafy plants they can hide under may be ideal, as they do like to hide and relax.

In terms of decorations, you should have quite a bit of them in your suckerfish tank. Like we just said, these guys like to hide from other fish and relax, which means that they like decorations. Now, these bad boys are pretty big, so you will need to find decorations that match their size.

Large pieces of hollow driftwood, large rock caves, and open castle-type things are all great. You need to leave a fair amount of open space for swimming, but a lot of caves and hiding spots are necessary too.

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Lighting For Suckerfish

Suckerfish don’t really like the light that much, especially Plecos. In fact, these fish are mostly nocturnal, which means that they feed at night and can’t see much anyway. The lighting is not all that important as long as you have the aquarium water at the proper temperature.

Sure, a decent aquarium light for fish is good, but it doesn’t need to be anything huge or overly bright. Just for a little pro tip, if you want to see your Pleco eat during the day, dim the lights so it comes out.

small black pleco
Image Credit: otsphoto, Shutterstock

Feeding A Suckerfish

Suckerfish are pretty convenient when it comes to feeding. They are technically omnivores and will eat extremely small fish and insects, but their main source of food is algae and plant matter.

Many people love having suckerfish because they work wonders in terms of algae control. They will scour the tank in search of some delicious algae to eat. They also enjoy eating the discarded food from other fish, as well as plant matter too.

Keep in mind that most aquariums out there, most likely all of them, simply do not produce nearly enough algae to keep a suckerfish well-fed, so you will need to supplement food for their diets.

What Do Sucker Fish Eat?

Since they are mostly herbivores, giving them some algae wafers is a good idea, but some shrimp pellets will work too. They will definitely enjoy things like fresh cucumber, lettuce, broccoli, zucchini, melon, and sweet potato.

Suckerfish eat from the bottom of the tank, so you will need to ensure that the food you give them sinks to the bottom, or else they won’t eat it. Also, make sure to remove excess food from the tank every single morning, as it will rot, decay, and make the water murky and full of unwanted naturally occurring compounds that you don’t want in there.

Feed them twice per day, but not too much. Give them a fair amount of food, and then if there are uneaten leftovers, you know that you can cut back a bit.

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Suckerfish Tank Mates

Suckerfish are generally quite friendly and peaceful as long as you don’t keep them with other suckerfish. They can be put into an aquarium with virtually any other fish out there, just not with other fish of the same species. They will get really territorial and start fighting each other.

Also, while Plecos or suckerfish are peaceful, if the tank is overcrowded, they will quickly turn into angry bullies and start taking it out on the other fish. You don’t want other suckerfish or other burrowing fish.

At the same time, suckerfish, while they are large, are not all that strong, so you don’t want to keep them with other large and aggressive fish. When it comes to larger and aggressive fish, the suckerfish is at a disadvantage. A few other tropical fish, preferably smaller and non-aggressive ones, are the best suckerfish tank mates to go with.

Image Credit: stockt0_0, Shutterstock

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Commonly Asked Questions

Why Isn’t My Sucker Fish Eating?

One of the reasons why your fish might not be eating is because you aren’t giving it the right food for sucker fish.

Generally speaking, some of their favorite foods include algae, algae pellets, algae wafers, and an assortment of fresh and blanched veggies. It could be as simple as that they don’t like the food you are giving it.

Of course, also beware that the right suckerfish food might not be the only way to get your suckerfish to eat.

Keep in mind that these fish are usually nocturnal, so they often won’t eat during the day either way, plus if they are new to the tank, stressed out, or sick, they may not eat due to any of these reasons.

Can Plecos Eat Zucchini?

Yes, some zucchini makes for a good occasional treat for plecos. Just make sure to peel the zucchini and then lightly blanch it in some boiling water, so it’s soft and tender, then feed it to your pleco in small chunks.

Can Plecos Be Kept Together?

For the most part, no, plecos should not be kept together with other fish of the same species. While young plecos tend to get along just fine, when they reach maturity, especially the males, they can become very territorial and aggressive towards one another. Plecos should not be kept with other plecos.

black pleco fish
Image By: koagulant, Shutterstock

Are Plecos Aggressive?

Generally speaking, plecos make for good community fish, when kept with other fish that are no plecos.

For some reason, plecos don’t get along with plecos, but that being said, as long as they have enough space, cover, and food, they are not aggressive towards other fish.

How Long Do Plecos Take To Grow?

What is interesting about plecos is that they never really stop growing. For the most part, they will reach maturity, and more or less their maximum size, within a few years of being born.

However, plecos will continue to grow slowly after that, albeit very slowly. That said, these fish, in their 20 year lifespan, can often grow to 2 feet or longer.

How Long Can A Pleco Live Without Food?

If your pleco is generally healthy and well-fed, it can go for about 7 days without being fed. That being said, of course, this is not healthy and should not be attempted.

However, they should be able to survive for roughly 1 week without being fed.

How Often Should I Feed My Pleco Cucumber?

Things like lettuce, zucchini, and cucumber should be given to plecos no more than twice per week.

Other than that, they should be fed specific pleco food designed for suckerfish health and nutritional requirements.

Albino Bristlenose Plecostomus
Image Credit: Ken Lord, Wikimedia Commons CC 2.0 Generic

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When it comes to taking care of suckerfish, it is not any harder than other tropical fish out there. Just ensure that the tank is large enough, the water conditions are right, that you have good substrate and ideal decorations, that you keep them with good tank mates, and that you feed them properly. As you can see, it is really not all that difficult.

Feature Image Credit: David Tadevosian, Shutterstock

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