How Long Does Prime Take to Work in an Aquarium

How Long Does Prime Take to Work in an Aquarium?

When it comes to cleaning your tank, using a product to dechlorinate the water is essential for fish keepers. Keeping your water pristine through water changes and siphoning the gravel isn’t enough. You need some way to dechlorinate the water and bind the ammonia.

With that in mind, what is Prime and how long does it take to work in an aquarium?

Prime is Seachem’s flagship product that removes chlorine, chloramine, and detoxifies ammonia, nitrite, and nitrate. It can be used in both freshwater and saltwater tanks and takes effect after 24 hours.

There are a lot of reasons why Prime is one of the top selling products on the market and is highly reputed among fish keepers. Down below, we’ll discuss exactly what Prime is, how long it takes to work, and how much of it you need.


What Is Prime?

Prime is a product that dechlorinates the water. In other words, it removes harmful chemicals, rendering them inert and safe for fish. 

The resulting chemicals are consumed by bacteria, expelling ‘the bad stuff’ from the tank. Because chlorinated water (aka your tap water) is harmful to fish, a dechlorinator like Prime removes them and binds them before these harmful agents can hurt your fish.

As such, dechlorinators like Prime are essential when introducing new water to your tank.

Can You Use Too Much Prime in an Aquarium?

Of course, the chemical agents used in Prime can be dangerous to your fish in high quantities. That’s why Prime has a recommended amount to put in per gallon (or liter).

A capful, according to Prime’s instructions, is suitable for treating 50 gallons or 200 liters of water. That’s about 5 mL of Prime.

Each cap thread is approximately 1 mL. It can be added directly to an aquarium but works best if you treat new water separately before adding it to a tank. There’s not really a concern for a Prime overdose in a tank since it’s nontoxic.

Pouring in an entire bottle isn’t wise, obviously, but the only recorded downside of massively overdosing with Prime is a decrease in oxygen in the tank.

For emergency detoxification of a tank, Prime allows for up to a 5x dose in a tank with no safety concerns, so it’d take a monumental overdose to start being worried about the effects of Prime in your tank.

The only feasible way you’d poison your tank with Prime is if you accidentally poured a whole bottle of the prime water conditioner in your tank.

You should take note that if your tank is above 86 degrees Fahrenheit (30 degrees Celsius), or if your chlorine or ammonia levels are low, then you should stick to a half-dose.

Is Prime Good or Bad?

Prime is a great product because is dechlorinates the water, making it safe for fish. Prime is perfectly safe to administer to a tank and has the added benefit of detoxifying the water and removing excess nitrites.

It won’t harm the cycling of your tank either. As it turns out, some test kits react with Prime, causing ammonia readings to spike. These, thankfully, are only false readings and aren’t indicative of any danger to your tank.

You may also wonder whether Prime is safe because it smells pretty bad (almost a sulfur-y smell) and forms salty deposits under the lid after you’ve used it. This is nothing to be concerned about either.

The smell and deposits are all expected under normal conditions and aren’t indicative that your bottle of Prime has gone bad.

How Often Can I Add Prime to My Aquarium?

According to Seachem’s website, you can add Prime every 24-48 hours into your tank, although you can certainly do it on an as-needed basis every time you do a water change.

Prime is non-toxic and doesn’t change your pH, so there’s no need to worry about overdosing as long as you stick to the recommended dosage and waiting period between dosages.

How Long Does It Take for Prime to Neutralize Ammonia?

One benefit of Prime is that it detoxifies as well as dechlorinating the water, binding ammonia, nitrates, and nitrites. This process can take up to 24 hours, but the product will begin working as soon as it enters the water.

After about 48 hours, the ammonia, nitrate, and nitrite are released back into the water, unless Prime is readministered to the tank.

Where Can I Buy Prime?

Prime is a widely available product sold by a lot of different sellers. You can find it in person in various different pet stores across the country, including PetSmart and Petco.

Online retailers also sell the product in various sizes for competitive prices. Amazon and eBay are two are the bigger sellers of Prime.

Seachem doesn’t sell Prime directly from their website, but you can see an overview of their product and get in touch with a dealer. To do so, you’ll need to navigate to Products and then Conditioners from the dropdown on the top right of their home page.

From there, select Prime and click Find a Dealer. This will open up a page where you can input your location and find a local place to buy Prime.

Seachem’s official website is also a great place to look for all of your conditioner needs for your fish tank.


Prime is a water conditioner that dechlorinates and detoxifies the water and is one of the leading products for both freshwater and saltwater tanks. It takes about 24 hours to work its magic in an aquarium and 48 hours to wear off completely.

If you’re using Prime, then there’s no real need to worry about overdosing as long as you stick within the recommended guidelines (conveniently labeled on the bottle).

Seachem doesn’t directly sell Prime, so you’ll have to shop online or visit your local pet store to pick up a bottle. If you’re looking for a great conditioner, Prime is a valuable option for every fishkeeper.