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Instant Ocean Sea Salt 50 Gallons, For Marine Aquariums, Fast Dissolving

  • Based on 8,264 reviews
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Size: 50 Gallon


Features

  • FORMULATED SPECIFICALLY FOR MARINE AQUARIUMS: Contains every major, minor and trace element delicate marine fish and invertebrates need.
  • DISSOLVES FAST: Superior solubility provides a clear, ready-to-use solution in minutes.
  • IDEAL pH: Quickly achieves and maintains ideal pH free of nitrate and phosphate.
  • CONVENIENT: No special additives are needed will not separate during packaging and shipping.
  • INSTANT OCEAN SEA SALT: The industry standard for quality, consistency and value for more than 40 years.
  • Instant ocean 50gal Sea Salt 3pc (Case)
  • Instant Ocean Sea Salt contains every necessary major, minor and trace element and has no nitrates and no phosphates
  • It was developed through sophisticated biological and chemical testing and every batch is analyzed to assure consistent high quality
  • Instant Ocean Sea Salt contains every necessary major, minor, and trace element and has no nitrates and no phosphates
  • It was developed through sophisticated biological and chemical testing, and every batch is analyzed to assure consistent high quality

Description

No matter the size of your aquarium, Instant Ocean® sea salts and water care products offer the smartest, easiest way to bring the ocean home. Our scientifically formulated sea salts are used exclusively by many of the leading large-scale aquariums and research facilities across the country. Instant Ocean® Sea Salt is the most carefully formulated, most universally preferred sea salt in the world. It’s the perfect solution for creating the ideal marine environment. Free of nitrate and phosphate, this sea salt formula contains every major, minor and trace element necessary for the health of even the most delicate marine fish and invertebrates. Its superior solubility provides a clear, ready-to-use solution in minutes, quickly achieving and maintaining the ideal pH. The sea salt withstands separation during packaging and shipping. For your convenience, no special additives are required. The consistent formulation is ideal for mixing small or large quantities. This sea salt is sealed to ensure freshness and ease of use. Mix Instant Ocean Sea Salt with ordinary dechlorinated tap water – for small quantities, use ½ cup per gallon of water. Stir vigorously to ensure a good mix. Use immediately or aerate the water until it achieves oxygen/carbon dioxide equilibrium. See product label for complete use directions. Instant Ocean brand offers a full line of products, including sea salt, water treatments, test kits and accessories, to make sure your saltwater aquarium remains vibrant and healthy.

Specs & Other Info

SpecificationDetails
BrandInstant Ocean
Liquid VolumeUp to 50 Gallons
Weight6.8 Kilograms (14.96 pounds)
FormStick
Applicable ForMarine Fish Species
Continuation StatusCurrently Produced
Product Dimensions11.81 x 1.97 x 14.57 inches
Recommended Age1 month and older
Model NumberSS3-50
Designed ForUnisex-Adult
Market Release DateOctober 2, 2001
OriginChina
Package Dimensions16.85 x 11 x 2.83 inches
ColorWhite
Volume Size50 Gallon Package
Material Compositioncotton (Packaging Material)
Suitable Age GroupAll Ages
Components IncludedInstant Ocean Sea Salt
Primary UseAquarium Salt for Marine Environments

Frequently asked questions

To mix Instant Ocean Sea Salt for your aquarium, first ensure you have the right amount of dechlorinated or reverse osmosis water for the volume you want to prepare. For a 50-gallon batch, measure the appropriate amount of salt using the guidelines on the packaging (usually around ½ cup per gallon of water, but this can vary). Slowly add the salt to the water while stirring to help it dissolve. Allow the solution to mix with a pump or powerhead until the salt is fully dissolved, which can take up to 24 hours. Make sure to check the salinity with a hydrometer or refractometer, adjusting as necessary to achieve the specific gravity recommended for your type of aquarium.

The ideal salinity level for an aquarium using Instant Ocean Sea Salt depends on the inhabitants of your tank. For most marine and reef aquariums, a specific gravity of 1.020 to 1.026 is ideal, which corresponds to a salinity of approximately 28 to 35 ppt (parts per thousand). It's important to check the specific needs of your aquarium's inhabitants, as some species may require higher or lower salinity levels.

Instant Ocean Sea Salt is specifically formulated for marine and reef aquariums and is not suitable for freshwater aquarium setups. Adding it to a freshwater aquarium would increase the salinity levels significantly, making the environment uninhabitable for freshwater species. For freshwater aquariums, it’s best to use conditioners and treatments that are specifically designed for freshwater habitats.

The frequency of water changes with Instant Ocean Sea Salt in your marine aquarium can vary based on several factors including tank size, number of inhabitants, and type of filtration system. As a general guideline, it’s recommended to perform 10-20% water changes every 2 to 4 weeks. Regular testing of water parameters can help determine the necessity of water changes more accurately. Always match the temperature and salinity of the new water to your aquarium's conditions to avoid stressing your aquatic life.

Top Amazon Reviews

🚀 Abunda's Overview

This is our summary and key points to consider based on customer reviews.


The collection of reviews for the Instant Ocean Sea Salt pinpoints it as a high-quality, cost-effective choice for both amateur and professional aquarium enthusiasts. Users highlighted its ease of use, effectiveness for breeding and growing brine shrimp, and superior hatching results compared to other brands. Despite a recent price increase, the consensus is that it remains a worthwhile investment for maintaining marine life.

Pros

  • 🐠 Arrives quickly and meets product descriptions
  • 📦 Well-packaged to avoid damage
  • 🧪 Easy to mix with accurate ratios for various needs
  • 💰 Cost-effective compared to in-store purchases
  • 🌊 Superior for hatching and growing brine shrimp
  • 🔬 Trusted by professionals for decades for breeding and maintaining marine life

Cons

  • 💧 Clumps and hardens easily if not kept dry
  • 💲 Prices have doubled in recent years

Should I Buy It?

If you're an aquarium hobbyist or professional looking for a reliable, cost-effective marine salt that promotes healthy marine life and is easy to use, Instant Ocean Sea Salt is highly recommended. Despite the price increase, its proven track record and user satisfaction make it a sound investment for your aquarium needs.


  • Still Among the Best Synthetic Marine Aquarium Salt after 5 Decades
I used to own a tropical fish shop, a commercial FW fish breeder and now just a retired hobbyist. I only use Instant Ocean salts to hatch and/or grow Brine shrimp now. I have always obtained superior hatches using marine salt mixes over rock salt. In the past, I've cultured some corals but a true measure of a marine salt mix is to have reef fish breed in captivity. I have had pairs of Yellowtail Blue Damsels, Chrysiptera parasema) breed almost every week for months at a time in the early 1980's. In a different setup in the late 1980's and early 1990's I had a 125 gal reef tank. Mostly corals with a few fish. In that tank, my pair of Pygmy Flame Angelfish, Centropyge loricula and trio of Mandarin Dragonets, Synchiropus splendidus, would regularly spawn just after the lights turned off. Of course, I never successfully raised any young because that is too difficult if one is landlocked with no access to tropical plankton to fee the young but some have been successful in tropical Pacific and Caribbean ora.com facilities. Most major public and commercial marine aquariums use Instant Ocean because it has high predictable quality at reasonable prices. ... show more
Reviewed in the United States on January 19, 2022 by Larry W

  • Saltwater salt is recommended
Size: 50 Gallon
Product is great came as expected and always works good with my saltwater fish tank would recommend; as it is cheaper here than the other two, well known pet stores by like $10
Reviewed in the United States on December 15, 2025 by Dan Rodgers

  • Great for a Reef Aquarium
Size: 200 Gallon
My fish are alive and this stuff is easy to use. I can tell it’s legit because it’s exactly what my local fish store uses (They have a lot of healthy saltwater fish). I do mess around with the amount per gallon and I don’t use exactly what the recommend, but my salinity is always spot-on. I like the individually packed bags. ... show more
Reviewed in the United States on May 4, 2025 by Else Else

  • Great stuff, used for 40 years or so exclusively
Size: 200 Gallon
I've used instant ocean for almost 40 years, from fish to reefs never had any issues.
Reviewed in the United States on December 21, 2025 by Buick48

  • Works good for 3 tanks
Size: 50 Gallon
This is the 2nd bag we have bought in the past year for my son’s 3 saltwater tanks. It keeps the water quality and ammonia levels where it should be. This is quick to react and doesn’t affect the color of the water. Keeps fish tanks healthy. Will buy again!
Reviewed in the United States on December 3, 2025 by William R.

  • Good
Size: 50 Gallon
Good
Reviewed in the United States on December 6, 2025 by Linda Rich

  • No problems at all
Size: 50 Gallon
I've been a saltwater hobbyist (45 gallon) for almost 10 years now and since the very beginning have been using this brand of salt with no problems at all. The pricing is always competitive compared to other name brands but the salt to me is always the same no matter which brand you go with. To mix this salt I use R/O water in a glass jar, pour in the salt and then fill with water. I shake it for a few seconds and let it sit till the salt dissolves. When the salt dissolves I start pouring slowly into the tank and measuring the salt amount with my meter. Other brand name salts that compare to this one are smaller grained and dissolve faster but for me, I have no issue waiting and I've noticed that on occasion over the years passed that if I do get impatient and pour some undissolved salt into the tank it doesn't seem to harm the fish or coral- some salts are not recommended to pour directly into the tank without dissolving first like I mention above in a glass jar with R/O water. Overall I favor this brand and have used it for so many years that switching now seems pointless. I'd recommend to others as I've had no problems with this product over the years. ... show more
Reviewed in the United States on February 10, 2017 by Cat Lady

  • Great Product
Size: 50 Gallon
Great supplement for hermit crabs salt water needs. Large bag lasts a very long time. Wish they still made the smaller boxes. Easy to use, goes a long way and do recommend.
Reviewed in the United States on September 5, 2025 by B

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