How do I take care of a red-eared slider?

At a glance

What you're signing up for

Start with the number that matters. Petco's own care sheet says 20 to 30+ years with proper care. National Geographic reports sliders can live up to 50. A turtle bought for a seven-year-old can still be alive when that child has a seven-year-old. This is the single fact most buyers do not know at the register, and it is why so many sliders end up abandoned.

The second fact is size. Hatchlings are the size of a coin. Adults reach 6 to 12 inches of shell. The hobby's tank rule is 10 gallons of water per inch of shell, which ReptiFiles calls the generally accepted minimum and Petco calls a good rule of thumb. Do the math on a 10-inch adult and you get a 100-gallon tank. ReptiFiles recommends 100 gallons minimum for any slider and 120-125 gallons (about 48 by 24 by 25 inches) for comfort. That is furniture-sized. It needs a filter, a heater, special lighting, and a floor that can hold the weight.

The third fact is what happens when people give up. Owners who discover the tank costs and the lifespan too late often release their slider into a local pond. Do not do this. It is illegal in many states, and it is why the IUCN consistently lists the red-eared slider among the world's 100 worst invasive species. Feral sliders now live in nearly every US state. If you cannot keep yours, rehome it through a rescue. Never release it.

Housing

Pet stores will sell you a 20- or 40-gallon tank as a slider setup. Petco lists 40+ gallons as a minimum. Be honest with yourself: that is a juvenile starting point at best, and the turtle will outgrow it. ReptiFiles, which calls sliders "among the most abused and underhoused reptiles," says 100 gallons minimum for any slider, with bigger always better. If you cannot house the adult, do not buy the hatchling.

The essentials:

• Water. At least as deep as the turtle's shell is long, and deeper is better. Water temperature 75-80°F, held there by a submersible heater.
• Filter. Rated for twice your tank volume. Turtles are messy, and dirty water causes shell infections.
• Basking dock. A dry platform where the turtle can climb fully out of the water and dry off. This is essential, not decor — it is how the turtle regulates its temperature and keeps its shell healthy. Basking zone at 85-95°F under a heat lamp; the cool end of the tank should not drop below the low 70s°F.
• UVB lighting. Full-spectrum UV light for 10-12 hours a day. UVB is the part of sunlight that lets turtles process calcium. Without it they cannot metabolize calcium, and the result is soft shell and metabolic bone disease. The bulb still looks fine when it stops producing UVB, so replace it every 6 months on a schedule, not by eye.

Feeding

Sliders change their diet as they grow, and this catches people out. Juveniles are mainly carnivorous — VCA Animal Hospitals puts animal protein at up to two-thirds of a young slider's diet. Adults shift toward plants. VCA says protein drops to about half; Petco puts vegetable matter at 50-60% of the adult diet. Feeding an adult like a juvenile, all protein, is one of the most common mistakes.

The staples are high-grade commercial turtle pellets and dark leafy greens: romaine, collard, mustard, kale. Iceberg lettuce is nutritionally empty — skip it. Treats stay under 10% of the diet. Juveniles eat daily; adults eat every 2-3 days. Some veterinarians recommend a multivitamin once a week and calcium twice a week.

One warning worth its own line: skip pet-store feeder fish. VCA reports feeder fish have been implicated as carriers of parasites and bacteria.

Never feed: - Iceberg lettuce (no nutrition) - Pet-store feeder fish (parasite and bacteria risk) - An adult a juvenile's all-protein diet

Health

The two problems slider owners actually meet:

Shell rot. A bacterial or fungal infection of the shell. The standard causes are dirty water and no way to bask and dry off fully. The fix starts with the setup, not medicine: clean water, a working filter, a real basking dock.

Metabolic bone disease. The soft-shell condition caused by missing UVB. Prevented entirely by a working UVB bulb replaced every 6 months.

Salmonella — read this part. Turtles carry salmonella bacteria as a matter of course, on their skin and in their water, without looking sick. As of August 2026 the CDC is tracking an active outbreak linked to small turtles: 8 cases, 3 hospitalizations, across 6 states — and every confirmed patient is a child under 10. The CDC's standing guidance: no pet turtles in homes with children under 5, adults over 65, or people with weakened immune systems. Everyone else washes hands after touching the turtle, its water, or anything in its habitat. Every time.

This is also why the 4-inch rule exists. Federal law has banned selling turtles with shells under 4 inches since 1975 (FDA regulation 21 CFR 1240.62), because small turtles get handled and mouthed by children. Tiny turtles are still sold illegally online, at flea markets, and at roadside stands. If someone offers you a turtle smaller than 4 inches, that sale is a federal crime and you should walk away.

Go to a vet today if: - Soft spots or fuzzy, pitted, or smelly patches on the shell - Swollen or crusted-shut eyes - Refusing food for days combined with lethargy - Floating lopsided, or gasping and stretching the neck to breathe - Any open wound

What it really costs

The turtle is the cheapest part. All Turtles' cost breakdown prices the animal at $10-$50 (rare color morphs run to $2,000). Then:

• Tank: $207-$1,800 (their baseline is a 55-gallon — note ReptiFiles would call that too small for an adult)
• Filter rated for twice the tank volume: $55-$155
• Heating — water heater, basking lamp, thermometer: $82-$140
• UVB lighting: $13-$50, and the bulb is replaced every 6 months at that price, forever
• Basking platform: $27-$75
• Water conditioner and test kits: $0-$40; optional substrate $0-$19; first food about $12

All Turtles' total initial setup: $411-$2,343. That is the honest version of the $10 turtle.

Ongoing, food is cheap — roughly $12-15 a year — but the UVB bulb repeats twice a year, and the heater, filter, and lights run around the clock. No source quantifies that electricity, so we won't invent a number, but it is the big recurring line most owners never budgeted. Reptile vet exams also cost real money; no reliable national figure exists, so ask a local exotics vet before you buy, not after.

Daily and weekly routine

Daily - Feed (juveniles); check the adult's feeding schedule (every 2-3 days) - Check water temperature and basking lamp - Skim visible waste and leftover food - Wash your hands after any contact with turtle or tank

Weekly - Partial water change - Rinse or service the filter as its schedule requires - Test water quality - Check the turtle over: eyes, shell, appetite

Monthly - Deeper clean of dock and tank surfaces - Check equipment: heater accuracy, filter flow, lamp timers - Every 6 months: replace the UVB bulb, no exceptions

Common mistakes

1. Buying an under-4-inch hatchling. That sale is illegal under federal law and those turtles drive salmonella outbreaks. Buy a legal-size turtle from a reputable source, or better, adopt from a rescue.
2. Starting in a 20-40 gallon tank and hoping. It gets outgrown fast. Buy the adult-sized tank first or don't buy the turtle.
3. Never replacing the UVB bulb. It stops making UVB long before it stops making light. Calendar it every 6 months.
4. No basking dock. The turtle must be able to climb fully out and dry off. Without it, expect shell problems.
5. Feeding adults an all-protein diet. Shift adults to 50-60% plants.
6. Feeding pet-store feeder fish. Documented parasite and bacteria carriers.
7. Letting small children handle the turtle. CDC guidance is blunt: not for under-5s, and handwashing for everyone else.
8. Releasing an unwanted turtle into a pond. Illegal in many states, and the reason this species is on the world's-worst-invasives list. Rehome through a rescue.

Is this pet right for you?

A good fit if... - You can house a 100+ gallon tank and pay for the equipment around it - You are ready for a pet that may outlive your dog, your lease, and possibly your career - You enjoy an animal you mostly watch and maintain, not one you cuddle - Everyone in the home will actually wash their hands

Think twice if... - You are buying it for a child under 5, or anyone in the home is over 65 or immunocompromised — the CDC says don't - You are picturing a small bowl on a desk - You cannot commit to decades, or to rehoming responsibly if life changes - The setup budget stops at the price of the turtle

Worth knowing

52 million exported. More than 52 million red-eared sliders were legally exported from the US between 1989 and 1997 alone, per IUCN figures reported by National Geographic. The pet trade in this species is enormous, and so is its castoff problem.

One of the world's 100 worst. The IUCN consistently designates the red-eared slider among the world's 100 worst invasive species. Ferals — nearly all of them released pets — are now established in almost every US state, including Hawaii.

The dumping goes back 90 years. Feral slider populations trace to pet releases documented since the 1930s, per the USDA's invasive species center. This is not a new problem; it is an old one we keep repeating.

Temperature decides sex. A slider hatchling's sex is set by the temperature its egg incubated at, not by chromosomes. This temperature-dependent sex determination has been the subject of NSF-funded research.

The 4-inch rule is 50 years old. Selling turtles under 4 inches has been a federal crime since 1975 — purely as a disease-control measure, after tiny turtles kept putting children in the hospital with salmonella.

It can outlive a large dog twice over. 20-30+ years typical, up to 50 possible. Write down who gets the turtle in 2050. That is not a joke; it is estate planning.

The 2026 outbreak's victims were all kids. In the CDC outbreak active as of August 2026, every confirmed patient was a child under 10. The hygiene rules are not fussiness.

What you'll need

• 100+ gallon aquarium — adult slider welfare minimum per the 10-gal-per-inch rule
• Aquarium filter rated for 2x tank volume — turtles foul water fast and dirty water causes shell rot
• Submersible aquarium heater — water must hold 75-80°F
• Basking dock/platform — turtle must climb fully out to dry, thermoregulate, and absorb UVB
• Heat/basking lamp — basking zone needs 85-95°F
• UVB bulb and fixture — required 10-12 hrs/day for calcium metabolism; bulb replaced every 6 months
• Aquarium thermometer (x2) — verify water and basking temps separately
• Water conditioner — tap water needs dechlorinating
• Water test kit — weekly water-quality checks
• Commercial aquatic turtle pellets — dietary staple alongside leafy greens
• Calcium and multivitamin supplements — per common veterinary dosing schedules
• Dark leafy greens (romaine, collard, mustard, kale) — 50-60% of adult diet (advice-only) (buy this where you already shop — we don't sell it, on purpose)

Browse the store for the gear above.

Sources