How To Setup A 100 Gallon Fish Tank

To all the home aquarium and fish tank fans out there, you’d want to stick with us on this one

A fish tank brings a whole bunch of possibilities for you to get creative and keep your favorite fish nicely tucked in.

If you were looking for ways to setup your 100-gallon fish tank, then this article is for you. Please note that we’ve mentioned 100-gallon and there’s a reason for that.

With the convenience, possibilities, and functionality a 100-gallon fish tank brings you, it’s the most widely opted choice for home-based aquariums by household consumers.

Aquariums, in the form of a 100-gallon fish tank, give personality to your home, while providing you with something mesmerizing and wonderful to look at.

Disclosure: This article contains affiliate links. When you follow a link to purchase the products, I sometime earn a commission, at no additional cost to you. Read my full disclosure here.

Let’s see how you can set up your very own 100-gallon fish tank.

Setting Up A 100-Gallon Fish Tank

As popular and evoking a 100-gallon fish tank looks, doesn’t mean that it’s an easy job to maintain it. It’s an expensive tank, requiring intensive care and consistent maintenance. But we bet you already knew that. So, if you’re ready to face the challenge of setting up a 100-gallon fish tank, follow through with the complete article.

Step 1 – Assembling the Tank

Assembling the Tank

Once you get your desired 100-gallon fish tank, the first challenge or part of the setup process that you’ll encounter, is assembling the tank itself. While the assembly process is simple enough for anyone to follow, there are a few things to pay special attention either to when assembling the tank:

  • Make sure that you attached the aquarium filter and the right one too
  • Make sure that the heater is equipped within the aquarium
  • Pay special attention to the lighting system of the aquarium
  • The Aeration mechanism or system should be intact and fully functional

Step 2 – Adding Substrate (Base) to Your Fish TankAdding Substrate (Base) to Your Fish Tank

If you’re relatively new to setting up a 100-gallon fish tank and not aware of what substrate is, then you simply need to understand that the substrate is basically the base of your aquarium or fish tank that serves as a resting or moving ground for living organism underwater.

Therefore, the next step that you need to take when setting up your fish tank, is to add the substrate in the base of your fish tank. However, as easy as it sounds, you need to make sure of the following:

  • Thoroughly clean the substrate with luke warm water before adding it to the fish tank
  • Make sure you cover the entire aquarium base and the thickness of the substrate or base is at least 1-inch of your fish tank’s base
  • Make sure to lay your fine substrate first and then add large grains as upper base of the substrate

Step 3 – Add Water to The Fish TankAdd Water to The Fish Tank

The next step of the setting up process of 100-gallon fish tank, is to add water to your fish tank. While this step is relatively simple, but there are some things that you’ll need to take note of when performing this step:

  • Once the fish tank is filled with water, you’ll need to adjust water quality
  • Make sure to add anti-chlorinators if you want a fresh water tank and marine salt if you want a salt water tank

Step 4 – Cycling Your Tank

Cycling Your Tank

Now comes the fun part. And don’t worry, you’re almost done setting up your 100-gallon fish tank. After you’ve filled your fish tank with water and added the substrate, now’s the time to cycle it.

Here’s how you need to cycle your 100-gallon fish tank:

  • Add required plants before the cycle (if they can withstand the cycling process)
  • Shifting water quality
  • Add delicate species after fully completed cycle
  • Cycle your tank for 6 to 8 weeks
  • Add your fish after the cycling process is complete

Step 5 – Adding Your Precious Fish

Adding Your Precious FishThe final step that you need to follow is to add your fish to the tank. The most intuitive and advised method is the floating bag method. It’s easy to use and very convenient, even for beginners. Here’s what you’ll need to do:

  • Start by floating your fish on the surface of your tank using a bag (the fish should remain inside the bag)
  • Use 25% of the water from your fish tank in the floating bag
  • See how your fish reacts to the change in water
  • Continue to add tank water to the bag after every 10 minutes or so and keep on administering the behavior or reaction of the fish to the new water
  • After completing one hour of this exercise, gently place your fish inside the tank (taking it out from the bag) through a net
  • Repeat the same process for every new fish you add to your tank


That wraps up our 100-gallon fish tank setting up guide. Hope you enjoyed setting up your very own 100-gallon fish tank, by following our step-by-step process.

Scott Evans

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