75-Gallon Aquarium Setup Guide

When it comes to big aquariums there are quite a few things to know, but luckily, once you have finished with the setup, and buying all of the accessories, the maintenance is fairly straightforward. You’re going to need a list of items to get your 75-gallon (or larger) aquarium outfitted, so we may as well start with your shopping list.

  • Your 75-gallon tank (not a kit but an actual, physical tank) that comes with a hood and a light, otherwise you’ll have to do the complicated setup and matching yourself.
  • A filtration system that is a minimum of 350 GPH (gallons per hour) and allows for the growth of that helpful bacteria we talked about earlier.
  • A heater that is made out of pretty much anything but glass and has 300w of power. Also, an important note for changing the water (in the section below): Turn the heater off or you’ll probably crack the glass.
  • A solid stand that will hold the fish tank, the water, and other accessories that go with your aquarium. That means that you’re going to need something that holds at least 500 pounds, and preferably tested for larger.
  • Gravel – go with a neutral color instead of hot pink or neon green. Your fish will appreciate it. It is also called “substrate” if you want to sound like you know what you’re talking about at the pet store.
  • A thermometer like the ones that float in the water or stick to the side and have a red substance inside to tell you the temperature. Don’ t get fancy because simplest is best here.
  • An air pump that is battery-operated or has a battery backup (in case the power goes out.) You’ll also need tubing and you’ll need an air stone.
  • A dechlorination solution is vital because the water from your sink is chlorinated for you to drink, but your fish require it to be clean of chlorine and other chemicals.
  • A chemical test kit. You’ll need to test quite a few things, some more than others: ammonia levels, nitrite and nitrate levels, water hardness and pH.
  • Live plants (unless you are planning to get fish that eat plants) that are specifically designed for use in a fish rank. You’ll understand why after you read the next section.
  • You’re going to need cleaning tools. At the very least, you’re going to need a scrubbing tool that you can reach far into the tank with.
  • Decorations are optional but can be good for fish so that they don’t get bored. Don’t go overboard and crowd the tank, however, because your fish won’t appreciate that.

Surprisingly, many people that buy 75-gallon aquariums are people that have never owned fish before. As the saying goes, go big or go home, and these fish owners are taking it to heart. For that reason, we’ll cover some basics of care in this article along with the specifics that come with having a tank that large. A lot of people make beginner mistakes that cost time and money, and that’s exactly what we’re going to help you avoid.

go big or go home

A Note to new Fish Owners

While it might seem simple to care for fish, there are a few things that you should keep in mind, and that doesn’t include all of the decisions that you have to make about choosing fish (i.e. freshwater vs. saltwater, how many, what kind and all that.) What you need to keep in mind is that fish are living creatures who have evolved with some pretty specific needs. You need to keep their needs in mind, and most of all, don’t forget them for long periods of time. This is a common problem with new fish owners. Unlike dogs and cats, fish aren’t going to be nosing their food dish across the floor or waking you up in the morning with their claws to demand food, a change of tank water or any of the other needs that they have.

Your Fish, Ammonia, Nitrites, and Bacteria

The first thing that you need to understand about taking care of fish is that you’re going to have to change the water. There is a complex explanation as to the reason why, which we’ll get to in a minute, but if you read nothing else in this section, please remember: you need to change the water regularly.

You see, fish suffer from what is known in fish keeping circles (yes, that’s really a thing) as The Nitrogen Cycle. Fish product ammonia. (Also, any food that you leave in the tank that doesn’t get eaten decays and produces ammonia which is also a good argument for not overfeeding.) You have probably opened a bottle of ammonia before and had it sting your eyes. Fish don’t like it any better than you do, but luckily, there are bacteria that will eat ammonia.

Unfortunately, the by-product of this bacteria are nitrites, which is harmful to fish as well, and the bacteria that consume nitrites produces nitrates, which are less harmful to fish but still cannot be allowed to accumulate. So, you have two options when it comes to getting rid of the final product: change out part of the water regularly and/or use plants to consume the nitrates and produce the oxygen that fish need. The rub is – some fish will eat live plants, and for those fish, you’ll have to do all the work yourself, and that involves changing out a portion of the water regularly. The best option is to get fish that don’t eat plants and change the water less often.

Step-by-Step Directions for Getting Started

Once you have everything that you have purchased assembled correctly then it’s time to go over some basics step-by-step. However, one note regarding putting everything together correctly: If you are building your aquarium stand from a kit (which many of them come in) then you’ll want to be absolutely sure that you get every screw and piece correct.

The result of a stand that isn’t put together correctly is 75 gallons of water all over your carpet.

Step One: Basic Electrical Safety

The only thing that you have to remember is that on anything that is inside the water as well as plugged in, you can’t let the water reach your electrical outlet, so the cord’s lowest point has to be lower than the plug so that the water can’t run down the cord to the socket.

Step Two: Tank Assembly

First, rinse the gravel using a strainer, a new one not the one you use for spaghetti and put it in something clean afterward. Then, put the aquarium on the stand and put the gravel in (gently so you don’t scratch the glass) and spread it out evenly on the bottom so that it is a couple of inches thick. Now, set up your filters (the user manuals are your friend; Google too) and attach all necessary equipment. Try to set it up so that you won’t have to move anything around when you do maintenance.

Step Three: Add the Water

Now, you can fill your tank with water. Try to use a small plate or bowl so that you don’t splash into the gravel and make it uneven. Make sure that there are no leaks as you fill it, and try to make sure that it is sitting as level as you can.

Step Four: Turn it on

When you have everything plugged in, the tank full of water and it is all ready to go, turn it on and let it run for three days to make sure that everything is working properly. Your heater should be set to about 78 degrees Fahrenheit for most freshwater fish.

Step Five: Check the Water Quality

Now, you’re going to want to test your water with the test strips you bought. You’ll want to make sure that it fits the parameters of the fish that you’re planning to get. Choosing fish is complex and requires a completely different discussion that we’re not going to have here. However, your local fish store will be able to tell you what you need for the type of fish that you are planning to get.

Step Six: Performing Maintenance

Once your fish tank is mature (meaning it is running like it is supposed to) you won’t have to worry about nitrite and ammonia. However, you’ll have to monitor nitrite levels, water softness or hardness and the pH of the water. Regarding the water changing instructions discussed earlier, remember that you’ll want to change some of the water whenever your nitrate levels start getting close to 40ppm. At that point, change 45-50% of the water. You’ll also want to remember that you should take your filter out and clean it manually with a toothbrush and replace carbon (other materials depending upon your manual) as necessary. Then, you’ll be all set to go buy your fish and put them in the tank!


Leave a Comment