Giant palythoa (Palythoa grandis) care guide

Group
Corals
Other names
Protopalythoa grandis, Giant palys, Palys, Button polyps
Family
Sphenopidae
Origin
Western Atlantic and Caribbean, from Florida and the Bahamas to the Lesser Antilles
Water
saltwater
Temperature
22–26°C
pH
8.1–8.4
Hardness
dKH 8–12
Care level
beginner
Reef safe
yes
Lighting
Moderate
Flow
Moderate

Care

Palythoa grandis is a large zoanthid: its polyps are wide and fleshy, about 2–3 cm across, with a ring of short tentacles. Unlike Zoanthus, its polyps are separate or only loosely joined. It is usually brown, tan or greenish. Place it low to mid on its own rock. LiveAquaria lists a palythoa relative as easy in care, with moderate light, medium flow and mid-tank placement, and says it spreads across the rock under good conditions. Water: LiveAquaria gives dKH 8–12, pH 8.1–8.4, specific gravity 1.023–1.025 and 22–26 °C, with iodine and trace elements. Naming: it is still often sold as Protopalythoa grandis; that genus was merged into Palythoa. Safety: zoanthids and palythoa can contain palytoxin, a dangerous toxin. Wear gloves and eye protection when handling or fragging them, and never boil, scrub or pressure-wash rock that carries them. Note: LiveAquaria covers only a relative, so the figures above are from that page, not from a source on this species. Not CITES-listed. Sources: LiveAquaria (liveaquaria.com/products/button-polyp-red-people-eater). Checked October 2026.

Diet

Photosynthetic, but larger palys feed readily. Offer mysis, brine shrimp or fine meaty foods once or twice a week.

Breeding

Very easy. Polyps multiply by budding. Cut individual polyps from the rock with a scalpel and glue them to plugs with cyanoacrylate gel. Wear gloves and eye protection, as this species is known to contain palytoxin.

Compatibility and tank mates

It has a weak sting but can crowd out neighbours as it spreads. Leave 5–10 cm of space. Some angelfish and butterflyfish eat 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.