Setting up a 20 gallon tank takes a little bit of time and effort but it’s not as complicated as it can seem. I recently upgraded my 10 gallon tank to a little 20 gallon Hexagon tank from Top Fin so I thought I would show you all the pieces and parts that make this little guy work.
If you’re researching how to set up a 20 gallon aquarium chances are you are setting up a brand new fish tank. While I do have a 55 gallon fish tank and a small 10 gallon I needed all new supplies sized specifically for a 20 gallon tank… so I was thrilled when my brother surprised me with this little 20 gallon Hexagon tank for my birthday!
I absolutely love aquariums that are slightly unusual sizes and a tall tank is my number one requirement since they take up less floor space than a long horizontal tank. When you’re trying to incorporate a fish tank into your home decor a tall tank takes up less space while still giving you room to house plenty of fish.
My new 20 gallon tank is actually a hexagon size so it’s tall and slender and being a 20 gallon it is able to rest easily on the dresser in my room. Make sure that if you are placing your fish tank on a piece of furniture it is able to withstand it’s weight… this dresser is solid wood and sturdy so it can easily hold about 225 pounds of water. If I were to place this tank on the smaller pre-fab dresser on the other side of the room we would probably have a different story.
Either way let’s get started with all the things you’ll need!
Picking Your New Fish Tank
First of all you need a tank… and probably an orange cat to sit nearby and watch the fish. Lily loves the new tank… just not the photos. If you choose to get a fish tank starter kit like my brother bought me then you should have everything you need already in the box… this little tank even came with a fish net and thermometer!
When picking a tank keep in mind the size of the fish you want to put in it… you can’t put a 6 inch fish in a 5 gallon tank. Of course, there are lots of factors that go into which fish can live in what size tank (water quality, tank makes, filtration, oxygen) but a general rule of thumb for newbies is 1 inch of fish for 1 gallon of water.
Don’t forget to take into account the full grown size of your fish… that cute little 1 inch fish at the pet store may grow to be a foot and a half. Most stores have adult sizes on their tanks but when in doubt ask… or even better look it up! Not all fish store employees are created equal (I bought 3 fish that were full sized instead of dwarf sized when I was starting out at the recommendation of an employee… these fish would grow to be 6 inches each instead of 2… yikes!). My brother (the fish dude) recommends checking Liveaquaria.com for info… so that’s what I do now.
So typically in a 20 gallon tank you could have 10 tetras which will grow to be 2 inches each. Just remember to do your research on the specific type of fish you are getting and their tank requirements. Experienced fish peeps will tell you the 1 inch per gallon rule is crap as alllllll of the other factors play a big part but it’s a good starting point and for beginner level fish like gourami, tetra, mollies or corydoras.
Led Lights for Day and Night
Okay there may be other important components for the fish but lighting is pretty important for the fish enthusiast… after all what’s the point of an aquarium if you can’t see the fish! Although there are plenty of lights available I love the Led lights that provide a white light for day and a blue light for night.
They are bright and clear during the day and provide a nice blue light at night so that you can still see the fishy’s but it’s less stressful for the fish. I have this light on my 55 gallon and my 20 gallon because it has a remote controller… so I can turn it off from bed when I’m done reading for the night. It also has lots of other colors (like pink!) which I love although it has a strobe option that I don’t understand… seems like that would give the fish little tiny fish seizures or something!
It’s best to turn your tanks off at night so the fish can have a bit of down time without a light on… it’s not great for the light to be on 24/7 even if they are in an office or living room and the light won’t effect you while you sleep.
My fish tank came with a built in hood to house the lights and cover the tank… it also has this little door at the front so you can feed the fish without taking the hood off. It’s super handy and lets you see the fish really good as they are eating. Score!
Adding an Air Pump and Bubbler
While my little tank may not need an air pump as much as a larger tank where the water is lacking oxygen I do like to put one in each of my tanks. First of all they’re cool. Second of all they help add oxygen to the bottom of the tank when you have a tall tank like I do.
I simply picked up a small air pump and a bit of tubing to attach to my bubbler. There are plenty of bubblers to pick from (my brother has a cute little barrel bubbler in his 30 gallon) but I stuck with my pink and blue theme and picked out this cute little pink coral bubbler.
It’s hard to see in the photograph but the air travels from the little air pump in the picture up above through the tube and into the pink coral where it’s released in bubbles that travel up through the tank providing the water with oxygen. I did get a shot of this little guy in action in the video at the bottom of the post.
Water Filter… because no one wants dirty water
Alright here’s the important part… the filter. Your filter determines how clean your tank will be and therefore how healthy your fish will be. The fish actually like a certain amount of algae… that’s good bacteria and is healthy for the fish. Uneaten food, fish poop, dirty sand… all of that is not healthy and the filter helps to… filter it out of the water.
Basically the better your filter the healthier the fish and the less water changes you will have to do. Now that’s what I’m talking about.
My bro said that you can never have too much filtration… typically he’ll use a 30 gallon filter on a 20 gallon tank, a 20 gallon filter on a 10 gallon tank. You get the idea! On his large 55 gallon he has two 75 gallon filters. Keep in mind that different fish have different needs… he has fancy, cool fish in his 55 that need a lot of filtration.
My 55 is set up for angel fish which are not strong swimmers and can’t handle a normal filter. I have a 55 gallon sponge filter set up for my sweethearts and it works perfectly… I also have about 10 panda corydoras in my 55 which are bottom feeders and help keep the tank clean. While I have a small chinese butterfly loach in the 20 gallon to add to the water quality. Bottom feeders are definitely a great addition to any tank and help keep all the fish happy.
Perhaps the next time I do a big water change I will show y’all how the sponge filter works and why it’s AWESOME! I had a hard time finding info on setting one up when I was starting out but it works perfectly.
Adding a little Water Heater
Since I have tropical fish these babies like their water in between 76 and 80 degrees. Without a heater the tanks in our home stay about 70 degrees so a little water heater makes these guys very happy. It’s an easy install and once you set the temperature doesn’t really require any maintenance.
Just make sure to turn it off during water changes since it really does need to be submerged when turned on and you’re good to go! If you’re looking to monitor it a little thermometer is the perfect solution and isn’t very invasive. Plus the fish seem to like looking at it… go figure.
Now you’re ready to add plants!
Plants, Decor and Sand to make your tank stand out
Most little fish like plants to swim around, caves to swim through, places to hide and typically a little decor to make their lives easier. Even schooling fish like tetras get along better when they have places to hide when need be.
Imagine if you were being chased around with no where to hide and no where to go. That would be horrible! Plus plants come in pink so……
This little 12 inch blue plant is one of my absolute favorites… the leaves are so pretty! You can see it peaking through the pink plant there in the back. I actually have roman columns in both of my tanks and love how the fish swim in and out of them… my alpha blue gourami has claimed one set as his territory in the 20 gallon. I caught a picture of him swimming around them this morning!
The last step is adding Water
Once your aquarium has sand it’s time to fill it with water… typically it’s easiest to add the plants and decor once the tank is about half way full of water. Although depending on your sand the water can get quite murky the first time you fill it and you may have to wait patiently for the water to settle.
I am not patient.
You’ll need to look into your specific fish and their water requirements but for my little guys tap water and a good water conditioner are all I need. This is the one my brother uses… and I steal from his room when I’m doing a water change.
When adding water to your aquarium pour the water onto a plate or flat surface instead of directly into the tank so that the water doesn’t disturb the plants and sand as much as possible. Of course, if you already have fish make sure they are safely out of the aquarium and in a bucket with water. Then once the water murkiness is gone you can add your fish!
All that’s left now is to enjoy! Here’s a little clip of my fish as I was feeding them this morning. Good luck setting up your new tank… leave a comment below on what type of fish you are going to have! I always like to hear about other people’s pets!
Psst… below the video is a little sneak peek of my 55 gallon… I’ll definitely be sharing that with you soon!
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