Instant Ocean Sea Salt for Aquariums, 160-gal

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$73.59 List Price
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About This Item

Details

  • Formulated to provide every major, minor, and trace element needed to support delicate marine fish and invertebrates.
  • The highly soluble formula provides a clear, ready-to-use solution in minutes.
  • Free of nitrate and phosphate, the salt quickly achieves and helps maintain a healthy pH value in your tank.
  • No special additives are needed—the convenient mix will not separate during packaging and shipping.
  • Instant Ocean Sea Salt is specially formulated for use in marine aquariums.

Instructions

FAQ

Learn More About Instant Ocean From Our Team of Experts

Questions & Answers

9 Customer Questions


How much salt do I put for a 29 gallon tank

Answer by ChewyMar 25, 2020
For tanks between sizes, we recommend the next largest size. Please click on the attached photo for detailed instructions.

Can this be used with invertebrates

Answer by ChewyDec 28, 2018
This product can be used with invertebrates but it should never be mixed in an aquarium containing animals. Always transfer animals to the aquarium after salt is completely mixed and aerated and specific gravity has been adjusted. To facilitate the growth of corals and other invertebrates in a reef aquarium, it's recommended to use Reef Crystals® instead.

is the 200 gallon box one big bag of salt, or is it 4 50 gallon bags inside the box?

Answer by ChewyOct 18, 2023
There are four bags of salt in the box. Each bag can make up to 50 gallons of salt water depending on the mixing method and type of water used.

Could this be used for a brackish tank?

Answer by ChewyJul 05, 2018
This product can be used in all saltwater aquariums.

4.7
Rated 4.7 out of 5 stars
404 Ratings

187 Customer Reviews



Rated 5 out of 5 stars
By Jessica on Oct 11, 2025

best marine salt for hermit crab saltwater pool

This is the best marine salt to use in our hermit crabs’ tank to create their saltwater pool. I have seen photos of Aquariums behind-the-scenes that use this in

This is the best marine salt to use in our hermit crabs’ tank to create their saltwater pool. I have seen photos of Aquariums behind-the-scenes that use this in their huge saltwater exhibits, too, so it’s nice to know we’re using what the professionals use!


Rated 5 out of 5 stars
By Carliejo on Nov 10, 2025

Instant ocean

I have used this brand of sea salt in my salt water fish tank every time I do my water changes. It does a great job. My fish stay healthy and happy. The price

I have used this brand of sea salt in my salt water fish tank every time I do my water changes. It does a great job. My fish stay healthy and happy. The price is right!! Thank You Chewy


Rated 5 out of 5 stars
By Mark on Nov 3, 2025

Good salt

I have used instant ocean for years and it is a decent salt. Decent price and fast free shipping.

I have used instant ocean for years and it is a decent salt. Decent price and fast free shipping.


Rated 5 out of 5 stars
By Joe on Jul 10, 2025

Instant Ocean Salt Mix

Instant Ocean (IO) continues to be a superior quality salt mix. Stability and consistency of desired water parameters is accomplished when mixing directions are

Instant Ocean (IO) continues to be a superior quality salt mix. Stability and consistency of desired water parameters is accomplished when mixing directions are followed. Parameter testing of pH, calcium, magnesium and alkalinity are consistent with various batches. In terms of pricing, IO is a solid value when prices are compared across various brands.


Rated 5 out of 5 stars
By Steven on Oct 22, 2025

Easy to order and fast delivery !

I don't like to fool around with cumbersome software or procedures and Chewy makes it easy.

I don't like to fool around with cumbersome software or procedures and Chewy makes it easy.


Rated 5 out of 5 stars
By Barry on Sep 9, 2025

Instant ocean

Been reefing for over 30 years and this is the only kind of reef salt I have ever used with my fish, soft corals and some monti caps.

Been reefing for over 30 years and this is the only kind of reef salt I have ever used with my fish, soft corals and some monti caps.


Rated 1 out of 5 stars
By Saoud on Aug 7, 2025

Order one box of salt, got three!

Ended up having to pick up two very heavy boxes of salt to facilitate the return and then had to waste time coordinating the return, which I have not received to

Ended up having to pick up two very heavy boxes of salt to facilitate the return and then had to waste time coordinating the return, which I have not received to date!


Rated 5 out of 5 stars
By Bruce on Sep 25, 2025

Best prices - quick shipment!

Instant ocean probably makes the best salt- and Chewy makes it easy and economical to buy!

Instant ocean probably makes the best salt- and Chewy makes it easy and economical to buy!


Rated 5 out of 5 stars
By Brandon on Jun 28, 2025

Great value & reliable

Instant Ocean is always the best value when it comes to salt for your tank, but it is also very consistent, and always reliable quality. A good product regardless

Instant Ocean is always the best value when it comes to salt for your tank, but it is also very consistent, and always reliable quality. A good product regardless of the price, but add in the affordability, and it's a great choice.


Rated 2 out of 5 stars
By Rosanne on Sep 25, 2025

it was delivered in a crushed box

it was thrown on my deck and the box was crushed lucky the salt was not compromised

it was thrown on my deck and the box was crushed lucky the salt was not compromised