Aquarium Livestock Pet Care Guides

Tunicates & Sea Squirts

Natural Habitat

Indo-Pacific, Atlantic

Tank Temperature




Specific Gravity



Filter-feeder; should be fed zooplankton or phytoplankton multiple times daily.


Constantly filters water through body in order to feed.


Reef Safe. Do not keep with aggressive tankmates.

Species Overview

Tunicates, Sea Squirts and Sea Pork appear to be simple organisms, but are actually Chordates, the same scientific classification includes all vertebrates (animals with backbones). These animals are extremely proficient filter feeders. A single tunicate can filter thousands of gallons a day and can extract almost all bacteria and plankton from the water to feed on as it filters. They need an almost constant food source to avoid starvation.

These animals are known as "sea squirts" because most will squirt water from their openings if threatened. Most tunicates have two main openings, one to "inhale" water and the other to "exhale". There are well over 1,000 species of tunicates and it can be difficult or impossible to tell the exact species of some individuals. Color, size and shape can vary on many species. Some of the larger tunicates may be collected for sale in the aquarium trade while other smaller species may come in as "hitchhikers" on liverock or corals.

Some common tunicates offered for aquariums include Golden Tunicates, Polycarpa aurata, which will shed its leathery skin periodically, and the colonial tunicate, Neptheis fascicularis, also known as the lollipop tunicate, that may pop off its siphon heads when stressed. They regenerate over the course of a couple of weeks.

We always suggest that you do further research before adding a new pet to your tank. What we have provided for you are guidelines and suggestions. If you have any further questions or concerns, please contact our fish room at 717-299-5691 ext. 1213 or

Recommended Items

Coral & Invertebrate Food
Protein Skimmers
Live Rock
Power Head