Round stingray (Urobatis halleri) care guide

Group
Marine fish
Other names
Haller's round ray, Little round stingray, California stingray, Spotted stingray, Cortez ray (trade name, confusing), Dwarf Cortez ray
Family
Urotrygonidae (round rays)
Origin
Eastern North Pacific from Humboldt Bay, California, to Panama, commonest off southern California and Baja; sand and mud, often with eelgrass, usually under 15 m.
Water
saltwater
Maximum size
58 cm
Temperature
12–22°C
pH
8.1–8.4
Hardness
Salinity SG 1.023–1.026
Minimum tank
680 litres
Care level
expert
Temperament
peaceful
Reef safe
no

Care

Tank: floor area matters far more than height. Give a deep bed of fine, smooth sand (at least 5 cm) to bury in, little or no rockwork, guarded heaters and pump intakes, a tight lid, and strong filtration and aeration, as rays are messy feeders. Avoid copper-based treatments, which rays and their relatives tolerate poorly. The list suggests at least 180 US gallons (about 680 litres); the article adds dim light and a gentle, even flow. Water: the article gives 12–22 °C, so this is a cool-water ray. pH 8.1–8.4 and SG 1.023–1.026 are general marine guidance; the article recommends dissolved oxygen of 7–8 ppm and iodine dosing to prevent goitre. Behaviour: new arrivals startle easily but tame with time. A sick ray turns pale grey and its markings fade. Active by day; digs pits to find buried prey. Disc width up to about 31 cm in females. Safety: the tail carries a venomous, serrated spine. A sting is very painful, though rarely dangerous to life. Never handle the ray by hand, net it with care, and get medical advice if stung. The spine is shed and replaced from time to time. Identification: sometimes sold as "Cortez ray", which causes mix-ups with Urobatis maculatus (that species has black spots on the sides of the disc). Conservation: IUCN Least Concern. Selling: our policies require the adult size and long-term tank needs to be stated clearly in the listing. Large fish must travel by a specialist live-animal courier (see the Livestock shipping guide). Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies); Wikipedia (en.wikipedia.org/wiki/Urobatishalleri). Checked October 2026.

Diet

Hunts bottom invertebrates: young eat worms and small crabs, adults mostly clams and other bivalves. Offer chopped clam, mussel, shrimp, squid and worms, using feeding tongs, about once a day or more in small portions.

Breeding

Gives birth to live young (aplacental viviparity), 1–6 per litter, usually 2–3, after about three months. Pups are 6–8 cm across. Females can store sperm; maturity at about 31 months.

Compatibility and tank mates

Not reef safe: eats crabs, shrimps, clams and worms, and may take small bottom fish. Keep with calm, cool-water fish that will not nip it or steal its food; avoid anemones and stinging corals that can injure it.

Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.

About Aquatic-Auctions

  • Aquatic-Auctions (aquatic-auctions.com) is a UK online marketplace for aquarium and pond livestock and equipment: tropical and marine fish, corals, shrimp, snails and other invertebrates, aquatic plants, tanks, filtration, lighting and food.
  • Items are sold by auction, buy it now or classified advert, by hobbyist and business sellers in the UK.
  • Buyers pay sellers directly; Aquatic-Auctions does not hold the money. Hobbyist sellers must offer PayPal and may also take cash on collection. Business sellers take PayPal (required) or cash on collection, and bank transfer only once they have a seller rating of 50 out of 100, a company and pet-selling licence checked by Aquatic-Auctions, a bank account in the company's name, and bank details approved by Aquatic-Auctions.
  • Buyers are told to pay by PayPal Goods & Services, never PayPal Friends and Family, gift cards or crypto.
  • Live fish and other vertebrates must be sent by specialist live-animal couriers (for example APC Overnight or DX Express), never by Royal Mail. Some invertebrates and plants may go by Royal Mail Special Delivery or 1st Class within its rules.
  • Banned and invasive species (for example those on the GB invasive species lists) cannot be listed, and sellers must meet the site’s animal welfare standards.
  • Members must be 16 or over to buy (16 and 17-year-olds with a parent or guardian’s agreement); sellers must be 18 or over.
  • Business sellers show their address, company details and pet-selling licence to buyers. Seller ratings run from 0 to 100: +1 for each positive feedback, −1 for each negative.
  • The site includes a free community species wiki with care guides (water parameters, tank size, diet, temperament, breeding).
  • Aquatic-Auctions is run by Etavonni Tech Limited trading as Aquatic-Auctions (company number 10204188), Aldershot, Hampshire, UK. Contact: info@aquatic-auctions.com.