Plecostomus are a subfamily of tropical bottom-dwelling sucker catfish native to South America that can grow up to two feet and will eat a very wide variety of foods, including vegetables, dead fish, algae (as discussed in a previous article, one pleco is capable of eating all of the string algae per 1,000 gallons of water), and mosquito larvae. They belong to the family Loricariidae, and are also known as armored catfish. There are more than 150 species within this family, meaning there’s quite a range of sizes, temperature tolerances, and temperaments.
One of the smallest pleco species, the white spotted dwarf (hypancistrus) pleco, reaches a maximum adult size of about 2.4 inches, while one of the largest pleco species, the adonis pleco, has been known to grow over a meter (39 inches) in size. Plecos in general grow quickly, and depending upon the species can grow up to a foot per year (even the smaller dwarf varieties will double or triple their size in just a few months to a year).
Overall, most plecos seem to get along just fine with other fish species but prefer to be the only one of their kind, so try to ensure that each pleco has adequate space (1,000 gallons of water per fish for larger varieties such as the common pleco, and at least 100 gallons per fish for smaller varieties like sailfin plecos). Some of the most commonly chosen pleco species for ponds and aquariums include the:
- Common pleco
- Bristlenose pleco
- Zebra pleco
- Vampire pleco
- Clown pleco
- Sailfin pleco,
- Snowball pleco
- Royal pleco
- Butterfly pleco
- Sunshine pleco
Can Plecos Survive Cold Water? Are There Cold Water Plecos?
As discussed above, plecos are a tropical species hailing originally from the freshwater streams and rivers of South America (specifically the Amazon River Basin), and as such are generally better suited to more mild waters. If kept outdoors, plecos do best in tropical to semi-tropical regions. They do just fine in temperature regions as well provided they are not left outside over the winter. Most plecos are tolerant of waters ranging from 65 to 85 degrees Fahrenheit (18-30°C), though they prefer temperatures between about 75 and 82°F (24-28°C). With that being said, there are some pleco species that are hardier than others, and may be able to withstand some cooler waters.
The common pleco is considered one of the most resilient, favoring temperatures ranging from 72 to 86°F (22 to 30°C) but able to withstand temperatures into the mid to low 60’s (15°C~) provided it’s not for an extensive period of time. Much below this, and they may start to develop health issues, become lethargic, may float up to the surface, and could die if low temperatures persist. Bristlenose plecos, despite their small adult size of only 3 to 5 inches, are a bit more cold resistant, able to survive water temperatures that fall into the 50’s (10°C~). Some have found sailfin plecos to be able to withstand similar temperature minimums as bristlenose plecos. Overall, plecos should not be left to overwinter outdoors if you don’t live in a warm region. To help plecos survive winters, you could utilize a pond heater or bring them inside to an indoor pond or aquarium, provided it’s large enough to house this hefty species. You will also need to be sure to not stress the fish when capturing it to move it, as this make them much more susceptible to illness and disease, and also makes it more difficult for them to adjust to any temperature differences in the water when you move them to a new container.
Considerations When Keeping Plecos In Garden Ponds
1) How Big do Plecos Grow? (Some, Quite Big!)
Before purchasing any plecos for your pond, there are a number of factors that should be taken into consideration. First off is their size, depending upon the species. As mentioned previously, some species can reach several feet in length while others may only be a couple of inches. For the larger plecos, you’ll need to make sure that your pond is large enough to accommodate them; for smaller plecos, you’ll need to be sure to place them with other fish that won’t eat them. You will also need to have an indoor space large enough to keep them during the winter if you live in a region where temperatures drop much below 60 degrees Fahrenheit.
2) Is Your Water Quality Good Enough?
Plecos are well known for their ability to consume large quantities of algae. However, they also generate a fair amount of waste, often more than they consume. This means having to clean your filters, pumps, and overall pond more frequently. It’s recommended to vacuum your pond and change 25 to 50% of the water on a weekly basis if you have plecos.
Since their natural habitat consists of freshwater rivers and streams, plecos do best in an environment that has plenty of aeration and water movement. Incorporating a small waterfall into your pond or simply using a high powered filter should both oxygenate the water and increase the current enough to suit plecos just fine. This may not, however, suit other fish species that prefer still waters, so you’ll have to do some research to figure out compatible fish species. They get along well with most other fish (except for their own kind), so the trick will be just trying to match up some basic habitat requirements. This includes a pH of 6.5 to 8, and a water hardness of 5 to 19° dH.
3) Do You Have Hiding Spots?
As bottom feeders, plecos like to lounge about at the bottom of water bodies, munching on algae and anything else they come across. They need hiding places as well as things to anchor themselves to; most pleco species really enjoy having wood in their pond or aquarium. They can anchor themselves to it, use it for hiding, obtain some nutrients from it, and the wood will also act to help keep the pH within the range that plecos survive best in.
4 ) Are You Choosing the Right Pleco?
You should also research different species, as they can differ widely in size and appearance. For example, snowball plecos are all black (or very dark), but covered in white spots that give them a polka dotted appearance. The golden nugget pleco is similarly dark, but covered in yellow-gold spots, with its fins and tail tipped beautifully in the same color. Sailfin plecos have, predictably, a very large dorsal fin and can range in patterning from spots to squiggly stripes to an almost camouflage pattern.
Overall, you should make quite certain that you’re aware of all of the requirements of a pleco, as well as the size that the particular species you have will reach. Many people get rid of plecos once they reach adulthood, releasing them into the wild as they become too large for the pond or too large to overwinter indoors without purchasing a more sizable container for them. However, unless one lives in South America, this is quite a bad thing to do, as plecos are an invasive species outside of South America. They are able to completely alter the trophic dynamic of an ecosystem as well as the nutrients available to native species, as they consume algae and out-compete other fish species, and are not highly predated on by other animals. They also generate a great deal of waste, thereby disrupting the water quality and existing ecological balance that native species in that area have adapted to and depend upon for survival.
I want to put my common pleco in my pond. Its unheated and unfiltered, its about 100,000 gallons, will he survive?
Hi Mark,
Plecos are originally tropical fish, so most don’t do well if waters fall below 65 degrees F. What is your average pond water temperature, and do you live in an area that has winter? If so, and as such the water in the winter gets cold or even freezes, you’ll have to bring the pleco indoors or it will become ill and could die. In terms of the size of the pond, that’s plenty of space!
Some ice fishermen catch common plecos so their temperature tollorence is massively under stated in the hobby. I’m thinking of putting 2 in my outdoor koi pond for a year to see what happens. I live in the north east of England and we can have some harsh winters.
Hope your right.. I’ve just bought a 30cm common pleco for my small lake 🤞🏼 I’m in Essex
Hi Chris,
How did the pleco do over winter?
Hi Stephen, I’m in the midlands and was considering one in my pond. How did yours do over winter?
How did your plecos do over the winter? I have one in my Koi pond but have not seen evidence that he’s still around.
I live in the Dallas area and unfortunately lost mine when the temps dropped this past winter. I will definitely be getting a better livestock heater this next winter so it won’t happen again.
I’m ion Dallas too. I have fish in my 15k gallon pool and want to put pleco in to help with the algae. What kind of heater are you using?
I’m in North Carolina zone 7b. We’re still experiencing 70 degree weather in the middle of November.
However, it’s dipped to 27 and in the low 30’s for a few days. I have a heater that comes on at freezing temperatures. When it began warming up I wanted to do a parcel water change in the fish tank and found the Plecko had died. He really grew over the summer. I was sad. I failed at it’s expense!
I don’t recommend taking the chance. I was hopeful, not selfish.
I was told at a fish store that it would survive. I don’t think your average Joe fish chains know anything about ponds and outdoor stock! Find a Pond guy or shop and get outdoor fish stock and guidance through them not someone who knows about indoor aquariums!
Please can you tell me how this worked out as I’m considering doing the same
I live in Canada should i buy pleco with my koi … all im asking is will they survive our winters they are harsh
Hi Donovan,
Plecos are not tolerant of cold waters so they shouldn’t be placed in your pond unless you are able to keep the water heated over the winter.
I purchased a snowball pleco for my small outdoor koi pond. He was about4 inches long. I live in Galveston Texas. Winters are usually mild, but we can freeze occasionally. I looked for him the next day, but couldn’t find him. I assumed a raccoon had gotten him. 16 months later, as I’m feeding my koi, a whale shark came swimming by!!! It was about 12 inches long! I guess he had been hiding all this time. It did get in The high 30’s last winter, so I’m assuming they are a little hardier than the experts state.
Hi Cheryl,
That’s amazing! I’m glad that, after all of that time, your pleco is alive and well! They really are pretty hardy creatures, especially if the water is a few feet deep so they are more protected from the cold in winter.
I live in Los Angeles so pretty moderate temperatures. Might have some nights in high 40s F but mostly around 60F. Do you think he would survive in a Koi Lind here? He is too big for my aquarium and I have a neighbor with large koi pond. Don’t know what kind he is but he is a yellow/gold/orange color
Hi Becky,
If the fish is a koi, they are fairly hardy and while they don’t prefer temperatures below 50F, they will simply enter a state of torpor in which they conserve energy when temperatures do drop. They are able to survive just fine for months like this, so long as the water doesn’t completely freeze, so a night here and there in the 40’s or 50’s will be just fine 🙂
If you’d like some further information on koi and their habitat/temperature preferences, here are a couple of our other articles: https://pondinformer.com/koi-vs-goldfish-guide/
https://pondinformer.com/how-to-keep-pond-fish-alive-winter/
https://pondinformer.com/best-pond-fish-types/
For tips on keeping koi alive and healthy during the winter, we have some articles on that, too!
https://pondinformer.com/how-to-heat-koi-pond/
https://pondinformer.com/koi-pond-winter-care-guide/
Hi,
I want to keep a Pleco fish.Can it survive in a tub of a few litres.It is quite small only about 4cm
Hi Parth,
That depends somewhat on the species! Common plecos are most often sold and purchased, and these grow fairly large. Sailfin plecos are smaller, but still would not do well in only a few litres. All plecos, regardless of species, also have particular water quality and dissolved oxygen needs. The tub could be a very temporary home if needed, but you’d need to have some form of aeration for oxygen, plants for hiding, etc. and I’m not sure that a tub would properly house those things. I would recommend a large aquarium if you are unable to have a pond, or forego having a pleco altogether.
I have a small goldfish pond, about 250 – 300 gallons. I live in south central Texas. We don’t don’t get extreme winters, but do occasionally have some below freezing temps at night. Which placo species would do best in this pond. I do have a couple submersible aquarium heaters I can put in if really necessary.
Hi Jenny,
Apologies for the delay in responding! For the size of your pond and occasional cold temps, I would recommend either bristlenose plecos or pitbull plecos. Neither of these species typically grow larger than about 3 inches in length, and are a bit more tolerant than some other species of cooler temps. They still prefer temperatures in the 70’s F, but can tolerate them dropping into the 50’s or even 40’s temporarily. I would encourage you to utilize your heaters, though, if you know that temperatures are going to drop!
I’ve got a Bristlenose plec,,, it’s about 10 inches long,, I had a red tailed black shark,, about 50cm,, all my other fish are small,,, but the shark kept invading its home,,, now the shark has gone,,, did it eat it??? Well it must have,,????
Hi there, have a lot of algae in a cattle trough (from being under a tree) here in aus north QLD, wondered if putting a couple of these guys in would do well? It’s a large concrete trough with about 10 head watering from it daily. Each cow consumes 40L a day so the trough is constantly being refilled and aerated from the constant filling.
The bore water which it runs off is perfect ph levels.
Would they do well in this environment?
Hi Toni,
Approximately how many gallons/liters is the trough?
This has me curious, a friend wants to get rid of an aquarium with fish and all. I want the tank for something else and not finding anyone for the fish yet. Was going to take the pleco which is about 7 inches long in a 10 gallon tank (!) and put it in 1/2 acre pond. Northern Ohio – I am hoping it will live pond is about 8 feet deep goes down some in the winter but bluegill, crappy, catfish have lived in it for years. We shall see.
So how did your pleco survive in the pond? I have a 75 gal. Tank and a 14 in pleco and he needs bigger tank. I’m thinking of a pond at church.
I have 4 Plecos in an outside pond which I heat over the winter. I live in Brisbane. Most websites suggest you can only keep one Pleco but I’ve kept my four together from day one. No bother at all. Love ’em!
Hi Jill,
That’s great!!! Every fish is certainly different, and we’re so glad that you’ve had success in keeping several plecos together!
Hi, I live in North West England UK, i have a common pleco in a tank indoors, however he is now about 30cm long and getting to large for the tank, i have a Koi pond outside that is 2 meters x 2 meters x 1 meter deep (approx 2000 litres), will the pleco survive in the pond?
Enjoyed reading your info on Plecos. We’ve had power failure over the last two days, and it’s got down to 3°C overnight. (Western Australia). Both Plecos are about 10″ long and we’re lethargic this morning. Have battery air supply, but no heater.
Hello! I have 3 Common Plecos in my 1000 gallon pond about
2 1/2 – 3 feet deep. They are about 10 inches and 7 years old. I live in Arizona and the temperature in the winter drops to below 40 but doesn’t freeze. Can they survive? And where can I find a submersible pond heater!!
I live in southern Portugal, which can get chilly at night at this time of year, but air temperature rarely drops much below 5ºC for very long. Do I need to bring my sailfish pleco inside or will he survive in those conditions?
Hi I live in GOOD OL’ kansas. I have a 4 foot small pound and I will tell you that I have always kept two common pleco in it all year round. they do just fine. Our weather here is crazy one min you will feel like getting into a pool the next min it is snowing. I move them out into the larger pond when they get too big for the smaller one or sell them to someone else looking for larger. They are more resilient than people are saying
I have 2 spotted Plecos, about a little over a foot long. They have been living in my 75 gallon tank for a couple of years now. I am needing to get rid of my fish, so I was wondering if they would survive in my friends pond? His pond is 15 ft deep. We live in Virginia near the North Carolina border and the temperature can get down below 32 degrees Fahrenheit. Will they survive the winter if I give them to him to put in his pond with the rest of my goldfish?
I live on the Georgia coast and I have 2 plecos in my 300 gallon outdoor porch tank. I just bought a heater that was stated to be used “for ponds” and when it came I read in the package that it is “ONLY FOR INDOOR USE”… well, that doesnt help me. What heater can I use for a 300 gallon pond that can keep the water warm enough for plecos that is rated for OUTDOOR use? I am so frustrated trying to find one. Its suppose to be 48 tonight and if this heater I just bought (a MantaMaze) had only been rated for outdoor use, it would be perfect. Now I am worried about my fish…
Hi Jennifer,
We have an article here covering some potential heaters that may be suitable: https://pondinformer.com/best-pond-heater-de-icer/
I’ve personally used both the Laguna and Oase models and can vouch for their reliability. Although they’re technically ‘de-icers’, since your pond is quite small, they should work well to create a warmer pocket of water for your fish to huddle around if things get too chilly. My koi usually hang out around the heaters during the coldest months of the year, and both models work well to keep the pond from freezing completely over.