What Saltwater Fish Eat Dead Shrimp: A Comprehensive Guide for Aquarium Enthusiasts

It’s a question many saltwater aquarium hobbyists ponder, especially those who dabble in feeding live or frozen options: What saltwater fish eat dead shrimp? The short answer is, quite a lot! In fact, dead shrimp, whether naturally deceased or intentionally thawed and offered as food, is a surprisingly versatile and commonly consumed item by a vast array of marine inhabitants. I remember the first time I cautiously offered a small piece of thawed shrimp to my budding reef tank. I was filled with a mix of anticipation and slight trepidation, wondering if my inhabitants would accept it, or if it would simply foul my water. To my delight, within minutes, a flurry of activity ensued, with various fish, and even some invertebrates, eagerly partaking. This experience sparked my curiosity and led me down a rabbit hole of understanding the dietary habits of our fascinating underwater companions.

Understanding what saltwater fish eat, particularly when it comes to readily available options like dead shrimp, is crucial for maintaining a healthy and thriving marine ecosystem in your home aquarium. It’s not just about keeping your fish alive; it’s about providing them with the nutrition they need to flourish, exhibit vibrant colors, and engage in natural behaviors. Dead shrimp, when prepared and offered correctly, can be an excellent source of protein and essential nutrients for many species. However, the “how” and “what” are just as important as the “if.” This article will delve deep into the world of saltwater fish diets, focusing specifically on their consumption of dead shrimp, offering insights, practical advice, and a thorough understanding of this common feeding practice.

The Omnivorous and Carnivorous Nature of Saltwater Fish

To truly grasp what saltwater fish eat dead shrimp, we must first appreciate the fundamental dietary classifications within marine fish populations. The vast majority of saltwater fish kept in aquariums fall into one of two broad categories: omnivores or carnivores. A smaller, but still significant, group are herbivores, though their interest in dead shrimp would be minimal to non-existent.

Carnivores: The Avid Scavengers and Predators

Carnivorous saltwater fish are those whose diets primarily consist of other animals. In their natural habitat, this translates to hunting smaller fish, crustaceans, squid, worms, and other marine life. When presented with dead shrimp, these fish often recognize it as a readily available, albeit deceased, food source that mimics their natural prey. Their strong predatory instincts might even kick in, and they’ll readily consume it.

Predatory Fish: Think of species like groupers, lionfish, snappers, and even some of the larger damselfish and wrasses. These fish have the jaw structure and digestive systems designed to process animal protein. A piece of shrimp is a welcome, and often easily digestible, meal.
Scavengers: Many marine environments rely on scavengers to clean up organic matter. Dead shrimp, unfortunately, represent organic matter. Fish like puffers, triggers, and some larger gobies are opportunistic feeders and will readily scavenge any edible material, including dead shrimp, that drifts into their territory.

Omnivores: The Opportunistic Eaters

Omnivorous saltwater fish have a more varied diet, consuming both plant and animal matter. This makes them incredibly adaptable and often the most enthusiastic consumers of a wide range of foods, including dead shrimp. They are less picky than strict carnivores and will exploit any available food source that provides nutritional value. Many of the most popular aquarium fish are omnivores.

Popular Aquarium Species: Many popular reef-safe fish, such as angelfish (though some are more omnivorous than strictly herbivorous), butterflyfish (again, species dependent), tangs (which have omnivorous tendencies despite their herbivorous reputation), clownfish, and gobies, will happily eat dead shrimp. They are often used to supplementing their diet with meaty foods, and shrimp fits the bill perfectly.
Flexibility in Diet: The omnivorous nature of these fish is precisely why they adapt so well to captive environments. Their ability to digest and utilize nutrients from both plant and animal sources makes them less susceptible to dietary deficiencies when provided with a varied diet that includes options like shrimp.

Herbivores: The Uninterested Parties

Herbivorous saltwater fish, on the other hand, subsist almost entirely on plant matter – algae, seaweed, and phytoplankton. They typically lack the digestive enzymes and intestinal length required to efficiently process animal protein. Therefore, dead shrimp holds little to no appeal for them. Tangs, rabbitfish, and certain damselfish fall into this category. While some tangs might exhibit omnivorous tendencies or nibble on detritus that could include tiny remnants of organic matter, they are not primary consumers of larger pieces of dead shrimp.

Which Saltwater Fish Will Eat Dead Shrimp? A Detailed Look

Now that we’ve established the dietary categories, let’s dive into the specifics of which saltwater fish are most likely to consume dead shrimp. It’s important to remember that individual preferences can vary within a species, and even within a single fish’s lifetime. Factors like the size of the shrimp piece, its presentation, and the overall hunger level of the fish can all play a role.

Popular Community Fish That Devour Dead Shrimp

Many of the staples of the saltwater aquarium hobby are enthusiastic eaters of dead shrimp. These are often hardy species that do well in a variety of tank setups and are a joy to observe feeding.

Clownfish (Amphiprioninae): These iconic fish are quite opportunistic omnivores. While their primary diet in the wild might involve zooplankton and algae, in an aquarium setting, they readily accept a wide range of foods. Thawed shrimp, chopped into manageable pieces, is a favorite for many clownfish. They’ll snatch it up, often carrying it to their host anemone for safekeeping or to “tenderize” it, a fascinating behavioral adaptation.
Gobies (Gobiidae family): This incredibly diverse family includes many popular species like watchman gobies, fire gobies, and neon gobies. Most gobies are opportunistic omnivores or carnivores. They are often bottom-dwellers or ambush predators and will readily consume small, appropriately sized pieces of dead shrimp that land near them. Some gobies are filter feeders, but many will readily pick at particulate food.
Damselfish (Pomacentridae family): While some damselfish can be territorial and aggressive, many are also quite eager to eat meaty foods. Species like chromis and some of the smaller damselfish are great candidates for accepting thawed shrimp. They are typically active swimmers and will dart out to grab any food morsels.
Cardinalfish (Apogonidae family): These often nocturnal or crepuscular fish are typically carnivorous or omnivorous. They often have large mouths and are adapted to feeding on small invertebrates and fish. Dead shrimp, especially when offered during their active feeding times, is a welcomed addition to their diet.

Larger and More Predatory Species

If you’re keeping larger, more predatory, or more specialized species, dead shrimp can also be a valuable dietary component. It’s crucial to ensure the shrimp pieces are appropriately sized for these fish to prevent choking or indigestion.

Angelfish (Pomacanthidae family): While the dietary needs of angelfish can vary by species, many are omnivores with a strong inclination towards meaty foods. Larger angelfish species will readily consume pieces of shrimp, often tearing off chunks that suit their size. It’s important to offer a balanced diet to angelfish, as some species can be prone to developing head-hole syndrome if their diet is too heavily reliant on meaty proteins without sufficient vitamins and minerals.
Butterflyfish (Chaetodontidae family): Similar to angelfish, the dietary habits of butterflyfish are diverse. Many are omnivores or specialized feeders. However, many common aquarium butterflyfish will readily accept thawed shrimp. As with angelfish, a varied diet is paramount to their long-term health.
Triggerfish (Balistidae family): These intelligent and often boisterous fish are generally omnivores with a strong preference for meaty foods. They possess powerful jaws and are well-equipped to handle a variety of textures. Dead shrimp is a staple for many triggerfish diets, providing essential protein and fats.
Puffers (Tetraodontidae family): Pufferfish are notorious for their love of meaty foods, and dead shrimp is a perfect fit. Their ever-growing teeth require constant abrasion, which is provided by tough foods, but they will also readily consume softer items like shrimp. Care must be taken with some species, as they can be prone to bloat if overfed with rich, meaty foods.
Wrasses (Labridae family): Many of the larger, more predatory wrasses, like the Coris wrasses or Hogfish, are carnivores or omnivores. They are active hunters and scavengers and will readily consume dead shrimp.
Groupers and Snappers: If you have a larger show tank with these magnificent predators, dead shrimp can be an excellent, easily digestible food source. Ensure the pieces are appropriately sized to avoid any issues.

Invertebrates That Also Benefit from Dead Shrimp

It’s not just the fish! Many invertebrates also find dead shrimp to be a desirable food source, acting as excellent scavengers in a reef tank.

Hermit Crabs: These mobile scavengers are tireless workers in the aquarium and will readily consume any edible detritus, including pieces of dead shrimp.
Shrimp (Peppermint Shrimp, Cleaner Shrimp, etc.): Yes, even other shrimp species will sometimes consume dead shrimp, especially if it’s a larger or deceased individual of their own kind or a similar species. This is part of their natural scavenging and opportunistic feeding behavior.
Snails (Astrea, Turbo, Nassarius, etc.): While primarily grazers, many snails will also scavenge. Nassarius snails, in particular, are excellent scavengers and will burrow into the substrate to find food, including dead shrimp.
Sea Urchins: Some sea urchins, especially if they are not getting enough algae, will readily consume meaty foods, including pieces of shrimp.
Starfish (some species): Certain predatory or scavenging starfish species will also consume dead shrimp.

The Practicalities of Feeding Dead Shrimp to Saltwater Fish

Simply tossing a whole, frozen shrimp into your aquarium isn’t always the best approach. There are several important considerations to ensure successful and beneficial feeding.

Sourcing and Preparation

The source and preparation of the dead shrimp are paramount to avoid introducing unwanted pathogens or chemicals into your system.

Quality Matters: Always opt for shrimp from a reputable source. For aquarium use, “human-grade” frozen shrimp from your local grocery store is generally safe. Avoid shrimp that have been treated with preservatives or antibiotics, though this is less common in basic frozen shrimp. Look for shrimp that are simply frozen, without added solutions.
Thawing: Never feed frozen shrimp directly. Always thaw it completely before offering it to your fish. You can do this by placing a small amount in a separate container of tank water or a small amount of fresh, dechlorinated water for about 15-20 minutes. Never thaw at room temperature for extended periods, as this can promote bacterial growth.
Rinsing: Once thawed, it’s a good practice to rinse the shrimp gently under cool, fresh (dechlorinated) water to remove any surface impurities or excess salts.
Portion Control: This is perhaps the most critical aspect. Only feed what your fish can consume within a few minutes (ideally 2-5 minutes). Overfeeding is a common mistake that leads to nutrient spikes, algae blooms, and poor water quality. Smaller, more frequent feedings are often better than one large meal.
Chopping and Mincing: For smaller fish or for better distribution, chop the thawed shrimp into smaller, bite-sized pieces. For very small fish or fry, you might even want to mince it finely. A clean knife or scissors works well for this. For larger predatory fish, larger chunks are appropriate.

Feeding Methods

How you introduce the shrimp to your tank can influence consumption and minimize waste.

Direct Feeding: For larger fish, you can sometimes hand-feed them using feeding tongs or a feeding stick. This can be a great way to build trust and observe your fish up close.
Broadcast Feeding: For smaller pieces or for distributing food to a larger population, gently drop the chopped shrimp into the water column. Try to do this when the fish are actively swimming and looking for food, often during the day for diurnal species.
Target Feeding: If you have specific fish you want to ensure get the food, or if you have finicky eaters, you can use a syringe or a pipette to deliver the food directly to their vicinity.
Frozen Food Mixes: Many aquarists prepare their own frozen food mixes, which often include chopped shrimp as a primary ingredient along with other marine proteins, spirulina, and vitamins. This ensures a well-rounded nutritional profile.

Frequency of Feeding

This is highly dependent on the species, the age of the fish, the overall size of the aquarium, and the presence of other food sources. However, a general guideline for most adult fish in a well-established aquarium is to feed once or twice a day.

Observe Your Fish: The best indicator of appropriate feeding frequency is the condition of your fish and the cleanliness of your aquarium. If your fish look healthy, active, and are not showing signs of starvation, and your water parameters are stable, you’re likely on the right track.
Avoid Overfeeding: This bears repeating. Uneaten food decays, consuming oxygen and releasing ammonia, which is toxic to fish. It fuels nuisance algae growth and can upset the delicate biological balance of your aquarium.

Potential Downsides and How to Mitigate Them

While feeding dead shrimp can be beneficial, it’s not without its potential pitfalls. Understanding these issues and how to address them is crucial for responsible aquarium keeping.

Water Quality Concerns

The primary concern with feeding anything, including dead shrimp, is its impact on water quality. Uneaten food and fish waste contribute to the nitrogen cycle, and if the system cannot process it efficiently, ammonia and nitrates can build up.

Ammonia and Nitrite Spikes: If too much shrimp is fed and not consumed, it will decompose, releasing ammonia. If your biological filtration is not robust enough, ammonia can build up to toxic levels, harming your fish.
Nitrate Accumulation: Even if ammonia and nitrite are processed, the end product, nitrate, will accumulate. High nitrate levels can stress fish and contribute to algae blooms.
Mitigation Strategies:
- Feed Sparingly: Only offer what your fish can eat in a few minutes.
- Remove Uneaten Food: If you notice uneaten food after 5-10 minutes, remove it with a turkey baster or net.
- Maintain Strong Biological Filtration: Ensure your aquarium has adequate live rock, a properly sized protein skimmer, and efficient mechanical filtration.
- Regular Water Changes: Performing regular partial water changes (e.g., 10-20% weekly or bi-weekly) is essential for exporting nitrates and replenishing essential trace elements.
- Use a Refractometer: Monitor salinity closely, as fluctuations can stress fish and affect their ability to process food.

Nutritional Imbalance

While shrimp is a good source of protein, relying on it as the sole food source would be detrimental. Marine fish require a diverse diet to obtain all the necessary vitamins, minerals, and fatty acids.

Lack of Essential Nutrients: Shrimp itself is not a complete food. It may lack certain vitamins (like Vitamin C or E) or essential fatty acids that are critical for fish health, immune function, and coloration.
Potential for Obesity or Digestive Issues: Overfeeding a rich, meaty diet like shrimp can lead to obesity in some fish or digestive upset.
Mitigation Strategies:
- Variety is Key: Always supplement shrimp with a diverse range of foods. This can include high-quality marine flake foods, pellet foods, frozen mysis shrimp, brine shrimp (fortified), spirulina-based foods, and live foods.
- Fortification: Consider using vitamin and mineral supplements designed for aquarium fish, especially if you are preparing your own frozen food mixes.
- Species-Specific Needs: Research the specific dietary requirements of the fish species you keep. Some have very specialized needs.

Introducing New Foods Safely

When introducing any new food item, including dead shrimp, it’s wise to do so cautiously, especially with delicate or newly acquired fish.

Start Small: Offer a very small piece initially to gauge their reaction and to see if it causes any digestive issues.
Observe Behavior: Watch your fish closely after feeding. Look for any signs of distress, regurgitation, or unusual behavior.
Quarantine New Fish: If you are introducing new fish, it is always recommended to quarantine them in a separate tank for a few weeks. This allows you to observe their health, treat any potential diseases, and introduce them to a varied diet in a controlled environment before adding them to your main display tank.

Frequently Asked Questions About What Saltwater Fish Eat Dead Shrimp

Here are some common questions hobbyists have when considering feeding dead shrimp:

How often can I feed dead shrimp to my saltwater fish?

The frequency with which you can feed dead shrimp depends heavily on several factors, including the species of fish you are keeping, their size, their age, their activity level, and the overall stocking density of your aquarium. For most adult fish in a community reef tank, feeding a small amount of prepared shrimp once or twice a day is generally appropriate. However, it’s crucial to adhere to the principle of *only feeding what they can consume within a few minutes*. Some fish, particularly very active predatory species or those with high metabolic rates, might benefit from more frequent small feedings. Conversely, less active fish or those with slower metabolisms may only require a single feeding every other day. Always err on the side of underfeeding rather than overfeeding, as excess food is a primary cause of poor water quality. Observing your fish for signs of good health and condition, and monitoring your water parameters, are the best indicators of appropriate feeding frequency. If your fish look plump and energetic, and your nitrates are within acceptable limits, you are likely feeding them correctly. If fish appear thin or lethargic, or if nitrates are consistently high, you may need to adjust your feeding schedule or the quantity offered.

Can I feed raw shrimp from my grocery store?

Yes, generally, you can feed raw shrimp purchased from your local grocery store. However, it’s vital to select the right type and prepare it properly. Opt for plain, frozen shrimp that are not enhanced with preservatives, phosphates, or antibiotics. Look for shrimp that are simply frozen. Rinse the thawed shrimp thoroughly under fresh, cool, *dechlorinated* water before feeding it to your fish. This helps to remove any residual salts, oils, or potential contaminants that might have been present during processing. While most common shrimp varieties like white shrimp or pink shrimp are suitable, always be mindful of any additives. If you are unsure, it is best to seek out shrimp specifically marketed for aquarium use, though these are often more expensive. The key is to ensure the shrimp is a clean, natural protein source. Avoid any shrimp that has been marinated, seasoned, or is sold in a solution you cannot identify.

What size pieces of dead shrimp should I offer?

The size of the shrimp pieces you offer should be carefully matched to the mouth size and feeding habits of your fish. For smaller fish species, such as clownfish, small gobies, or chromis, you will need to chop the thawed shrimp into very small, bite-sized pieces. Using a sharp knife or scissors and mincing the shrimp finely is often necessary to ensure they can swallow the food easily without risk of choking or internal damage. For medium-sized fish like angelfish or butterflyfish, slightly larger, diced pieces are appropriate. These fish can handle chunks that are roughly the size of a pea or slightly larger. For larger, predatory fish such as groupers, lionfish, or large wrasses, you can offer larger chunks, but it’s still advisable to avoid feeding whole, excessively large shrimp that could pose a choking hazard. If you have a mixed community tank with fish of varying sizes, you might need to offer a variety of sizes, or chop enough smaller pieces to ensure everyone gets a chance to feed. It’s always better to err on the side of pieces that are too small rather than too large. You can always offer larger pieces later if your fish demonstrate they can handle them. The goal is for the food to be readily consumed and easily digestible.

What are the nutritional benefits of feeding dead shrimp?

Dead shrimp, when sourced and prepared correctly, offers several nutritional benefits for saltwater fish. Primarily, it is an excellent source of high-quality animal protein, which is essential for muscle development, growth, and overall bodily function. Protein is the building block for tissues and enzymes. Shrimp also provides fats, which are crucial for energy storage and the absorption of fat-soluble vitamins. It contains a range of essential amino acids that fish cannot synthesize themselves and must obtain from their diet. Furthermore, shrimp provides a source of chitin, which is a component of its exoskeleton. While fish do not derive significant nutritional value from chitin itself, it can aid in digestive health for some species by acting as a prebiotic or roughage. However, it’s important to note that shrimp alone is not a nutritionally complete food. It may be deficient in certain vitamins (such as vitamin C, which is often degraded in frozen foods) and essential fatty acids like omega-3s, which are vital for immune function, coloration, and overall health. Therefore, it should always be part of a varied and balanced diet that includes other marine-based foods, such as mysis shrimp, brine shrimp, marine algae, and specially formulated flake or pellet foods, to ensure all nutritional requirements are met.

Are there any fish that absolutely should not eat dead shrimp?

Yes, there are certain categories of saltwater fish that should not be fed dead shrimp, or at least only in very limited circumstances and with extreme caution. The most obvious group are strict herbivores. These fish, such as many species of tangs (though some have omnivorous tendencies), rabbitfish, and parrotfish, have digestive systems adapted to processing plant matter. They lack the necessary enzymes and intestinal tract length to efficiently digest animal protein. Feeding them shrimp could lead to digestive upset, bloat, and potentially serious health issues. Even tangs, which may nibble at detritus, are not designed to consume significant amounts of meaty food. Another consideration is fish with highly specialized diets. For example, some butterflyfish are corallivores (eating coral polyps) or sponge-eaters. While they might opportunistically try a piece of shrimp, it’s not their natural or ideal food source. For these specialized feeders, it is always best to replicate their natural diet as closely as possible. In general, if a fish species is known to be a strict herbivore or a highly specialized feeder, avoid offering dead shrimp. Always research the specific dietary needs of your fish species before introducing new foods.

What are the signs that my fish have eaten too much shrimp?

Recognizing the signs of overfeeding, especially with rich foods like shrimp, is critical for maintaining a healthy aquarium. The most immediate and obvious sign is the presence of uneaten food floating in the tank or settling on the substrate after a reasonable feeding period (typically 5-10 minutes). If you consistently see leftover food, you are overfeeding. Beyond uneaten food, other signs can manifest in your fish themselves and the overall water quality. Your fish might appear lethargic or bloated, especially if they have consumed too much rich food and are struggling to digest it. Some fish might exhibit signs of digestive distress, such as unusual swimming patterns or even regurgitation. On a broader aquarium level, consistently overfeeding with shrimp or any other food will lead to elevated nitrate levels, which can contribute to nuisance algae blooms (e.g., hair algae, cyanobacteria). In severe cases of decomposition of uneaten food, you might notice a drop in dissolved oxygen levels or even cloudy water due to bacterial blooms. Monitoring your fish’s body condition—they should look healthy and active, not emaciated or excessively fat—and maintaining excellent water quality are your best defenses against overfeeding.

Complementary Foods for a Balanced Diet

While dead shrimp is a useful component, it should never be the sole food in a saltwater aquarium. A truly healthy and vibrant marine ecosystem requires dietary diversity. Here are some excellent complementary foods:

Frozen Mysis Shrimp: A staple in most marine diets, mysis shrimp are packed with protein and essential fatty acids. They are generally well-accepted by a wide range of fish and invertebrates.
Frozen Brine Shrimp: While often considered a “junk food” if fed alone, brine shrimp can be a good occasional treat or a vehicle for delivering supplements. Always purchase “gut-loaded” or fortified brine shrimp, or soak them in vitamin supplements before feeding.
High-Quality Marine Flake and Pellet Foods: Many commercially available marine foods are formulated to provide a balanced blend of proteins, vitamins, and minerals. Look for those with marine-based ingredients like fish meal, krill, and spirulina.
Nori (Seaweed): For herbivorous and omnivorous fish that consume algae, offering sheets of dried nori (sushi seaweed) is an excellent way to provide essential vitamins and fiber. You can use a clip to attach it to the glass or a rock.
Live Foods: While more labor-intensive, live foods like live brine shrimp, mysis, or specialized copepods can be incredibly beneficial for stimulating natural hunting behaviors and providing highly digestible nutrition.
Formulated LRS Foods or Similar: Brands like LRS (Living Reef Specialties) offer high-quality, pre-made frozen food blends that are designed to be nutritionally complete and are very popular among experienced aquarists.

Observing Your Fish: The Ultimate Guide

Ultimately, the best way to understand what your saltwater fish eat and how much they need is to observe them. Pay close attention to:

Feeding Frenzies: A healthy fish will eagerly dart out to grab food when offered.
Digestion: Observe their waste. Healthy waste is typically firm and well-formed.
Body Condition: Are they looking lean and healthy, or are they becoming overly plump?
Activity Levels: Healthy fish are generally active and engaged.
Coloration: Vibrant colors often indicate a well-nourished fish.

Your fish will tell you what they like and what they need if you take the time to watch them. The offering of dead shrimp is a common and often very successful practice in the marine aquarium hobby, providing a valuable protein source for many species. By understanding the dietary needs of your inhabitants, preparing food correctly, and feeding judiciously, you can effectively utilize dead shrimp as part of a balanced and nutritious diet for your beautiful saltwater aquarium.

From the smallest damsel to the most imposing grouper, the marine world is replete with creatures that appreciate the readily available sustenance that dead shrimp can provide. It’s a testament to the opportunistic nature of many fish and the efficiency of decomposition and scavenging in aquatic ecosystems. As aquarists, our role is to harness these natural processes responsibly, ensuring that our offerings contribute to the health and vitality of our captive environments, rather than detracting from them. So, the next time you ponder the fate of a thawed shrimp in your tank, remember the diverse array of life that might be eagerly awaiting it, and approach feeding with knowledge, observation, and care.

Conclusion: The Humble Shrimp’s Role in the Saltwater Aquarium

In conclusion, the question of what saltwater fish eat dead shrimp reveals a broad spectrum of aquarium inhabitants. From the vibrant clownfish that playfully snatch morsels to the powerful jaws of triggerfish and puffers, dead shrimp serves as a vital and frequently consumed food source. It underscores the opportunistic and often carnivorous or omnivorous nature of many popular marine fish. However, the successful integration of dead shrimp into an aquarium diet hinges on careful preparation, portion control, and a commitment to variety. By mitigating the risks of overfeeding and water quality degradation, and by supplementing shrimp with a diverse range of high-quality foods, hobbyists can harness the nutritional benefits of this humble offering. Ultimately, understanding and observing your fish remains the most effective strategy for ensuring they receive a balanced diet that promotes health, vitality, and the dazzling display we all strive for in our saltwater aquariums. The simple act of offering a piece of dead shrimp, when done thoughtfully, can contribute significantly to the well-being of your underwater charges, reinforcing the intricate relationships between food, fish, and the aquatic environment.

What Saltwater Fish Eat Dead Shrimp: A Comprehensive Guide for Aquarium Enthusiasts