How To Introduce Guppies to a New Tank

What You'll Learn

How To Introduce Guppies to a New Tank

A Step-By-Step Guide To Start Your First Aquarium

All the Equipment You Need

Learn How To Introduce Guppies to a New Tank

In this guide, I’ll teach you everything you need to know about how to introduce a guppy to a new tank.

Without further ado- let’s get started. 

How To Introduce A New Guppy To A Tank

Setting up a guppy tank takes about 15 days.

Now, you are probably thinking: “15 days?!?!”


But the truth is that it takes about an hour of work spread over those 15 days. 

The reason it takes so long to set up your tank is because this is how long it takes for your water the get conditioned and your filtration system to kick into action.

Step 0: Don't Buy Any Fish

Yes- you read that right.

You’ll have to wait about 2 weeks before any fish can go in the tank.

The reason why you can’t just put your guppies in is because the water will deteriorate very quickly.

Why Wait 2 Weeks Before Introducing Guppies To A New Tank

The reason you’d want to wait 2 weeks before you introduce a new guppy to a new tank is because of something called a nitrogen cycle. 

In simple words, a nitrogen cycle works by having your biofilter breakdown the naturally occurring ammonia in your tank. 

The catch is that it takes at least 2 weeks for the tank to run empty before your filter “gets seasoned”. 

The Chemicals In Your Water in 60 Second

Ammonia is harmful to fish- it can kill them.

But ammonia is naturally occurring because it’s a byproduct of decomposing fish food and fish poop. Since it’s unrealistic you’d be changing the water every single day- the filter comes to the rescue.

The filter works by sucking in water from the tank that contains ammonia. 

Inside the filter, there’s positive bacteria- a colony of organisms that will break down the ammonia and turn it into nitrite. But the problem is that nitrite is every more toxic to fish than ammonia. 

This is why the filter, within the same breath, will then convert the nitrite into nitrate.

Guppies are a lot more tolerant of nitrate, and plants can use it as a nutrient as well.

Pro Tip

Cycling your tank (i.e. running a nitrogen cycle, or letting your filter get seasoned) helps prevent New Tank Syndrome- a situation where ammonia and nitrite build up quickly and kill your fish. Because the positive bacteria in your filter hasn’t developed yet it can’t effectively filter naturally occurring ammonia.

You’ll know you have New Tank Syndrome if your water becomes cloudy and smells bad.

Your fish, obviously, can’t survive in conditions like those. 

It’ll take about 2 weeks before your tank becomes ready. On average, this is how long it takes for the positive bacteria to build up. 

First Steps

Remove the tank from the packaging. Remove the tank from the box and remove all packing material. You want to have a plain, clean tank. Don’t worry- washing it isn’t necessary. 

Place the tank where it’ll live. We’ve covered why you don’t want to put your tank near a window before, and you need to consider if it’s by an ac or heater. Those might add a cool/ warm breeze that might affect water temperature.

You’ll also want access to at least 1 electrical outlet. A guppy tank needs at least 3 available sockets to plug in the lights, filter, and heater. 

Rinse the Substrate. Using hot water and nothing else (no soap or other fun stuff from under the sink) rinse the gravel and decorations. This will remove dust and particles that might find their way into the water.

Add the substrate. Be careful when you place the substrate in the tank. Your tank is made of glass and substrate is usually rock or other hardy material. 

Add Water. filling the water slowly will help avoid cloudiness. With that said, in the first couple of weeks cloudy water is natural. Add the dechlorinator and any additional water treatment. Just read to labels before you do- as mixing the additives has to be done correctly. 

Turn on equipment. Turn on the filter and water heater. That will start the nirogen cycle.

Add Plants.

Pro Tip

Add a little bit of fish food into your new tank. It’ll break down into ammonia which will jumpstart the biofilter. You can also buy beneficial bacteria on its own and add it to speed things up.

And Now, We Wait

It is going to take about 2 weeks for an eco-system to grow inside your tank- enough for it to regulate itself.

In those 2 weeks, you still what to test the water to get a better understanding of what’s going on inside the tank. 

Test your water every 3 days. I use a 5 in 1 kit to give me the ammonia and nitrite levels. 

As long as you see ammonia and nitrite above 0 ppm (parts per million)- you can’t put any fish in.

After the first 5 days of your tank tank running an nitrogen cycle change 50% of the water.  Replace it with freshly conditioned water. 

Allow the tank the cycle for another 5 days. Continue to test the water in between to see where levels stand.

Do another water change of 50%, and let the tank run for another 5 days. 

After the 3rd time you let it run, do another water change. 

Now you can introduce your guppies. 

The timeline to set up a guppy tank is about 15 days or 2 weeks.

Sand substrate is the simplest type of substrate for a guppy tank. Other types include rocks, pebbles or plants.

A tank must be conditioned to remove ammonia and chlorine, as those can kill your fish.

How To Add Your Guppies In The Tank

Your guppies should come in a bag. if you ordered them online- there’s a good change they came in some very blue water.

Blue water is typical- it’s water treatment with medication to prevent water stagnation during shipping

Start by keeping the bag closed. Don’t open it to air yet. 

Allow it to float in your tank. That will allow the water of the bag to match to the water of the tank and help prevent shock. Let the bag float for about 20 minutes.

Pro Tip

Don’t allow water from the bag to seep into the main tank. You want to isolate the shipping water and dispose of it. If you pour it into the tank you may introduce diseases into your tank. 

Open the bag after 20 minutes have passed, but don’t put the guppies in the new tank just yet.

Using a cup, add water from the tank into the bag. That will allow the fish to acclimate to the new water chemistry. Add about a 1/3 of the bag volume with tank water. 

Allow the guppies to acclimate for 10 minutes, and then add more tank water. Give your guppies another 10 minutes to acclimate. 

After 2 stages of adding water and letting them acclimate- use a scooping net and transfer your guppies into the tank. 

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