Here’s how it works:

• Your fish poops, plants shed bits, and leftover food breaks down. This all creates Ammonia, which is highly toxic to your Betta.
  
• Then, a type of good bacteria converts that Ammonia into Nitrites (still toxic for your Betta!).
  
• Next, another type of bacteria turns Nitrites into Nitrates, which are much safer, but still only in small amounts (ideally under 2.5 ppm for Bettas, but we’ll come onto that later).
  
• So the goal is always 0 Ammonia, 0 Nitrites and a small amount if Nitrates.

You keep these toxins in check with regular water changes, which is swapping out some of the old water for fresh, dechlorinated water.

We need to dechlorinate the water because chlorine and heavy metals are harmful to Bettas and fish.

The best way to dechlorinate your water is to use a water conditioner like Seachem Prime. Here’s a quick breakdown of How to Condition Water for your Betta.

You’re thinking: Okay, but I have a new tank, how do I start this cycle?

How do I get the bacteria in the tank?

How do I know when it’s cycled?

All great questions.

We will answer all of them. But before we dive in, you should know there are two different ways to “cycle” your tank.

Two Ways to Cycle Your Tank

There are two main ways to cycle:

• Fishless Cycling (cycling your tank BEFORE you get your fish, which we highly recommend!)
  
• Fish-In Cycling (if you already have the fish, don’t panic, it’s still possible, but we only ever recommend this if absolutely necessary)

Now, think back to the nitrogen cycle. It kicks off with Ammonia. Then the bacteria convert that ammonia…

So, to start any cycle – whether it’s fishless or fish-in – you need two key ingredients.

You guessed it!

Ammonia and Bacteria

Ammonia & Bacteria Sources

AMMONIA SOURCES

Step 1 of the cycle we need to add ammonia.

In a fish-in cycle (which we don’t recommend unless it’s truly an emergency), your fish is the source of ammonia, through waste (eg. poop). So we don’t need to add any.

(That also means your Betta is exposed to toxic water while you try to build up bacteria. Not fun. Not safe. Only do it if you’re in a jam.)

But! In a fishless cycle, we need to add ammonia manually.

Two options.

We can use a bottled ammonia solution (like Dr. Tim’s Ammonium Chloride) or by “ghost feeding” (dropping in fish food and letting it rot).

bacteria SOURCES

Good bacteria are the heroes of your cycle!


These beneficial bacteria turn ammonia into nitrite, then nitrate — making your tank safe for your Betta.

There are three ways you can add them:

Great.

Now that we have the Ammonia and Bacteria that we need to start our cycle, here is a step by step guide to cycling your tank: Fish-less and Fish-in.

The Safe Bet: Fish-less Cycling

This method gets your tank ready before adding your Betta, aka the safest, cleanest way to set up their future home. Here’s what you’ll need:

• Liquid test kit (for ammonia, nitrites, and nitrates) like the API Freshwater Master Test Kit or NT Labs Liquid Test Kit. This tests for Ammonia, Nitrites, Nitrates, Ph, etc.
  
• A source of ammonia (like Dr Tim’s Ammonium Chloride or a pinch of fish food)
  
• A bottled bacteria starter like Dr. Tim’s One and Only or FritzZyme 7 (or pre-cycled filter media)
  
• Dechlorinated water (yep, you need to fill the tank before you cycle it!). As we said before, the easiest way to do this is with a water conditioner like Seachem Prime.

Steps to Cycle a tank Fish-less

Add your substrate first (remember to rinse it according to the packaging instructions).

Add decor and your filter and heater.

Forget what you’ve heard about Bettas not needing a filter or a heater – it’s not true!

A simple air pump and sponge filter will work, as well as a heater set to 78-80F.

Fill your tank with dechlorinated water.

As we said, the easiest and best way to do this is with a water conditioner like Seachem Prime.

Take your chosen ammonia source and add ammonia to reach about 1–2 ppm.

If you’re using a solution like Dr Tim’s Ammonium Chloride (which we recommend), just follow the dosing instructions.

Here’s a rough guide depending on the size of your tank.

Once we add our ammonia, we need to add our bacteria source.

You don’t technically have to add a bacteria source. The bacteria will grow naturally, just more slowly and so it will take you longer to cycle your tank.

So, if you have one, pop in your bacteria starter!

Depending on the product you chose (live bacteria, shelf-stable bacteria or a pre-seeded sponge ) dosing will be different.

Just follow the instructions on your chosen product.

Now it’s time to play aquarium scientist!

Testing is how you know your cycle is actually working and when it’s safe to add your Betta buddy.

The fishless cycling process can take anywhere from 2–6 weeks, depending on your bacteria source and temperature (warmer tanks cycle faster). Patience is key!

Start testing 24 hours after adding your ammonia and bacteria.

That gives your microbes time to wake up and start snacking!

Test too soon, and you’ll likely only see ammonia – no signs of the cycle kicking off yet.

After that, test every 1–2 days to track your progress. It’s exciting to watch nitrites appear, nitrates rise, and your tank move closer to being Betta-ready!

What to Test For:

• Ammonia
• Nitrite
• Nitrate
• pH
• Chlorine (only at the start or after water changes)

We’ve already covered how ammonia, nitrite, and nitrate power the nitrogen cycle – but don’t forget about pH!

High pH (combined with warmer temps) makes ammonia more toxic, so if you have hard water, even a little ammonia can hurt your Betta.

This is why regular water testing is so important. 

What to expect as you cycle your tank:

Remember: every tank is different! Your timeline might be faster or slower depending on bacteria type, temperature, and tank size.

Once you’re consistently seeing ammonia = 0 and nitrite = 0, it’s time for your tank’s graduation ceremony:

1. Add a full dose of ammonia (2 ppm)
2. Wait 24 hours
3. Test your water

If you get:

• Ammonia = 0
• Nitrite = 0
• Nitrate = present

Congratulations! Your tank is fully cycled and ready for your Betta!

Safe Water Parameter Ranges
for a Betta Fish are:

> PH: 6.5-7.5 > Ammonia: 0ppm > Nitrite: 0ppm > Nitrate: <20ppm

Fish-In Cycling: Only If You have to!

If you’ve already added your Betta and didn’t cycle first, don’t panic!

You can still make it work, but you’ll need to be extra diligent:

• Add bottled bacteria daily
  
• Test ammonia/nitrite levels daily
  
• Do a 25–50% water change any time ammonia or nitrite gets above 0.25 ppm
  
  (Why it matters: Even small spikes in ammonia or nitrite can burn your Betta’s gills, damage their immune system, and make them feel super stressed. Frequent partial water changes help dilute those toxins while you wait for your bacteria buddies to catch up!)
  
• Never skip a test day!

Your Betta’s health depends on it.

Final Checklist Before Adding Your Betta (Fish-less Cycle)

1. Test your water: ammonia and nitrites = 0, nitrates between 10–40 ppm
   
2. Match temperature to your tank (78–82°F)
   
3. Optional: Do a partial water change to bring down nitrates if over 40ppm
   
   
   

Perky Tip! While nitrates are safer than ammonia or nitrites, high levels can still stress out your Betta over time. A 30–50% water change (rough estimate) before adding your fish helps bring those nitrates into the sweet spot. Under 20 ppm is ideal for Bettas long term. why this matters Why this matters: Your tank may be technically cycled when nitrates hit 10–40 ppm, but your Betta will be happiest and healthiest in water with under 20 ppm. Think of this as your final polish before rolling out the red carpet for your finned superstar! Now your Betta can dive into their new home safely!

Frequently Asked Questions

Your Top Questions About Cycling—Answered!

How long does cycling a tank take?

 

 

How do I know when my tank is cycled?

 

 

Do I Need Ammonia and Bacteria Sources?

 

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Do bettas need a filter and heater?

 

What temperature should the water be for my Betta?

 

Betta fish are tropical fish, they like it warm and cozy!

• Ideal range: 78–80°F (25.5–26.5°C)
• Safe range: 76–82°F (24.5–28°C)

A heater is a must in most homes, even if your room feels warm to you. Consistency is key — sudden swings in temperature can stress your Betta.

What’s the minimum tank size for a betta fish?

 

Perky Takeaway

Cycling takes a bit of patience, but it’s 100% worth it. A cycled tank keeps your Betta healthy, active, and glowing with fin-tastic confidence. You’ve got this! And if you still aren’t sure – drop us a comment below and we’ll answer you as soon as we can!