How to Use Seachem Stability to Speed Up Fishless Cycle

Disclosure: I may earn a commission when you purchase through my affiliate links. As an Amazon Associate I earn from qualifying purchases. – read more

Any good, stable, and thriving aquatic setup begins with a well-designed cycling process. There’s no escaping the cycling routine since it’s what provides your tank with the biofilm necessary to remove ammonia and nitrites.

The bacteria from cycling your aquarium turn these chemicals into nitrates that plants use as nutrients.

The problem is that the cycling process can sometimes last 2-4 weeks or even longer. Many aquarists have reported a 6-8-week timeframe for the entire process to complete.

But there are ways to accelerate the cycling process a bit and this is where Seachem Stability comes in. So, let’s talk about that!

What is Seachem Stability?

Seachem Stability is pretty much a bacterial blend that you add to your tank to speed up the cycling process considerably.

The solution contains 4 types of beneficial bacteria:

  • Two of them are called nitrifying bacteria. These consume the ammonia resulting from decaying organic matter in the tank. Ammonia is defused and transformed into either nitrites or nitrates, depending on the species of bacteria you’re using.
  • Another type of bacteria consumes waste and turns nitrites into nitrates. The latter is less toxic, as most aquarium fish can withstand concentrations up to 20 ppm.
  • Finally, the 4th type consists of denitrifying bacteria. These consume nitrates and turn them into nitrogen gas.

All four bacterial organisms are necessary to promote a stable and healthy aquatic setup. They will form naturally in any aquatic environment over time, provided the right resources are there (organic matter and nutrients for the most part).

The only difference is that Seachem Stability allows you to skip the entire wait-for-the-bacteria-to-form phase.

The product will simply add the fully-formed bacteria to your tank to speed up the cycling process dramatically.

When Should You Use Seachem Stability?

The ideal time to use Seachem Stability is when you first start your tank before adding any fish or plants.

That’s because the cycling process relies on adding ammonia to the environment to feed the billions of bacteria ready to flood the water.

Seachem Stability Dosage

The official dosage recommendation is 1 capful for every 10 gallons of water. This is the initial dosage during the first day.

After the initial 24 hours, the maintenance program kicks in, during which you need to add 1 capful of Seachem Stability daily to every 20 gallons of water. The maintenance phase lasts approximately 7 days.

Using Seachem Stability for Fishless Cycle

Now that you know what Seachem Stability is and how it works let’s see how you should use it.

The cycling process consists of several steps:

  • Prepare the tank – You add the substrate, add any decorations and rocks, and pour the water. Do it gently to prevent disturbing the substrate, and don’t use chlorinated tap water. Chlorine will kill your fish and your beneficial bacteria at the same time.
  • Tweak the water temperature – Nitrifying and denitrifying bacteria require warmer waters to thrive. The tank’s temperature should revolve around 80-87 F to allow the colonies of bacteria to take over.
  • Add nutrients – You can use a pinch of fish food in this sense, although some people claimed to have used ammonia. The idea is to provide the incoming colonies of bacteria with the sustenance necessary to develop and multiply. You should keep using fish food or ammonia supplementation daily for the following 6-7 days while also supplementing the environment with Seachem Stability.
  • Turn off the UV filter – UV filters destroy bacteria since they function as sterilizing components. So, you should have your filter turned off for the entire 7-day period, which is what it takes for the cycle to complete. After that period, you can turn your UV filters on if necessary. The beneficial bacteria would have flooded the environment by this point, so they most likely spread everywhere. Some will die, but not all.
  • Add Seachem Stability – Once the tank is set up and all parameters are in place, add your first dose of Seachem Stability. Remember the dosing recommendations I’ve provided earlier: 1 cup per 10 gallons of water on the first day, 1 cup per 20 gallons of water daily for the following 7 days.
  • Wait and watch – You can consider the tank successfully cycled once the ammonia and nitrite levels show 0, with nitrates being no higher than 20 ppm. Reaching this point usually takes several days to a week, but it may last longer. If ammonia and nitrites are still above 0 by the 7-day mark, keep the cycle going. It will eventually end.

Remember: water changes are necessary to dilute excess nitrates, which will accumulate past the ideal value of 20 ppm.

How Long Does it Take for Seachem Stability to Work?

For the most part, the tank should be cycled within the first week of using Seachem Stability.

However, there are no absolute certainties here. It may sometimes last longer, so be ready for that.

The best part about using Seachem Stability, though, is that you can add your fish to the environment from day one.

That’s due to 3 things:

  1. Seachem Stability is fish-safe – The product won’t hurt the fish in any way. Even more importantly, there’s basically no danger of overdosing. Adding more Seachem Stability to your tank water will simply result in more beneficial bacteria flooding the environment. There’s nothing wrong with that.
  2. The presence of bacteria – You can’t add fish in an uncycled tank because such an environment has a lot of ammonia and no beneficial bacteria to break it down. But, with Seachem Stability, you have all the beneficial bacteria you need. Ammonia levels may increase temporarily, but the added Seachem Stability will diffuse it immediately. So, your fish should be fine.
  3. The extra poop – Adding fish to the habitat ensures a healthy dose of fish waste being produced daily. This will further feed the nitrifying bacteria, contributing to the cycling effect. You will also feed your fish every day, with any food leftovers further aiding in the process.


You can easily cycle your tank without Seachem Stability. You can do it with or without fish, as both work just as well.

The difference is that Seachem Stability speeds up the process considerably with virtually no downsides.

Author Image Fabian
I’m Fabian, aquarium fish breeder and founder of this website. I’ve been keeping fish, since I was a kid. On this blog, I share a lot of information about the aquarium hobby and various fish species that I like. Please leave a comment if you have any question.
Questions and Answers
Deborah from Kansas November 7, 2022 Reply

I have one aquarium that is about a month old, a 20 gallon. It STILL is not cycled though I do my prime and stability in it every day. I have quite successfully started other tanks this way. There is only one organism. My ammonia is .25 but nitrates 20, but nitrites about 50 to 80. It should have cycled well before now. It was supposed to be a glowfish tank, and I fear use of the lights to look at the decor may be the problem? Too much UV?

Leave a Comment

Your email address will not be published. Required fields are marked *