Inside Wall Aquarium Blog

Tips for DIY "Built in fish tanks".

Home » 2015

It’s ok, your aquarium can be deeper than your wall

It’s true a 5” or 6” wall aquarium can hold most pet fish species however, a bigger aquarium can hold more.  You can put a deeper aquarium in your wall by having one or both sides overhanging.  This can be done by having a base underneath 1 ½” thick and firmly secured to the wall studs below.  You will not need any additional supports as long as your overhang on one side doesn’t exceed 2”.  If you want one side to hang out more you will need to add some triangular/gusset pieces to support the base.


Inside Wall Fish Tank Gallery

This gallery contains 1 photo.

Here’s a great gallery of various inside wall tanks.  Hopefully these will help you picture a wall tank in your house.  Some are bigger than others but all basically are the same installation configuration.  

Who will install my tank?

HandymanMikeCostanzaTruckYou want a wall aquarium but are not handy or just don’t have the time.  In this case you will have to hire a local contractor.  Each product on our website ( has a link to its instructions on the product page.  You can print these off and bring them to contractors for quotes.  Contractors can be found online, in your phone book or on Craigslist (not recommended).

Contractors will charge by the hour ($50 – $100 typically) or job ($800 – $1500 for a wall aquarium).  A red flag might be no website, no good references (family/friends do not count) not answering the phone as a business (thank you for calling…), not insured or bonded.

A typical install can take 1.5 to 3 days.  Some maybe longer with custom trim work etc…  You get what you pay for so maybe the cheapest is not the way to go.  The aquarium must be on a flat surface, can be scratched and any electrical should be GFCI so pay close attention to these details.

Wall aquarium fish.


The general rule for fish in a thinner tank is to make sure the fish will not grow too long.  Your fish should have at least a 1” space between them and the walls however 2 ½”+ is recommended.  That means that if your tank is 6” deep you should have fish 3 ½” or smaller or if your tank is 8” deep your fish should be around 5 ½”.  The good news is that most aquarium fish fall under this category.  You can refer to these charts to help you choose.

6” tank depth

8” tank depth

Basic install.


To put a tank in your wall you are going to need some experience with electrical and knowledge of how a stud wall is built.

Plan out your wall opening.  Is your tank going to sit flush or hang-out on one side?  You are going to need to leave a gap on the left and right side of the tank.  If you have a hanging filter that gap will have to be large enough for it.  You will also need a minimum space of 5” above the tank.    

Next open you wall.  Secure your stud work around the tank to support it and the wall above.  Make a nice flat base with plywood and shims.  If the tank is hanging out of your wall the base will have to hang-out too. 

Now run your electrical wiring.  Place an outlet in one or both top corners of your opening.  Do not place it in the center because it might get in the way of the light.  Use a GFCI outlet, it’s important. 

Next clean up your drywall.  Mud, sand, mud again, sand again and paint.

At this stage you can put the tank into your opening and box it in with some trim.  Make your own from wood boards or use premade baseboard trim.  If needed you can make the top piece of trim removable or hinged so you can get in to feed and clean the tank.  The larger the opening the easier it is to get your hand in.  Keep in mind that you will have to cover the opening with trim so if it’s too large the trim looks odd.  A 6” gap is what we recommend.

That’s it.  A more detailed set of instructions can be found here:


In-Walls VS Wall Mounts.

vs3Wall mount tanks and In-Wall aquariums are similar but very different.  Let’s examine.  Both look cool, have a nice viewing area, have light, filter and heater but that’s where the similarities end.  An In-wall aquarium gets built into your wall while a wall mount hangs more or less like a picture.  A fish tank built in can be much larger meaning much larger and more fish.  In fact since a wall mount hangs it does not have enough support to hold much water and therefore it’s extremely limited.  It may look cool but ultimately not be satisfying with your fish options.

Another major difference is the finished look or wow factor.  A built in tank with the front flush with the wall looks awesome!  Now finish both sides and peer through the aquarium between rooms.  This is the ultimate fish tank.  You can think of a wall mount as a toy compared to a flush see through in-wall tank.

Of course the wall mounts have some pros.  It’s much easier to install.  Typically you might be adding some screws or plywood to the wall and an electrical outlet but not much else.  A built in tank requires more labor, materials and know-how.  A typical built-in tank can take 2 days compared to 2 hours.  A built-in might cost more in the end but if you’re doing the work yourself it’s not much different.

Obviously I am recommending a built-in tank.  I have one, I love it!  But I am handy and have the experience to do all the work myself.  If you do not have the know-how or can’t be bothered to go through the work than an unsatisfying wall mount might be for you.


Load bearing walls.

openDo you want a wall tank but have concerns or don’t know if your wall is load bearing?  The good news is that you can install an aquarium into a load bearing wall.  The key is to transfer the load around the tank.

First you start by building temporary supports in front or behind the wall.  The can be done with some vertical 2 x 4’s or 2 x 6’s and a header stud firmly against the ceiling.  These supports will take the load above while you cut into the wall.

Next you are going to open your wall up larger than your finished opening and fasten all the studs together with a footer and header stud.  If the wall is under load beef up the header with a couple 2 x 6’s on their sides and if possible put some studs directly under them to transfer the load to the floor.

Once everything is secure remove your temporary wall and you’re done this part of the project.

Does a wall aquarium have to be in a wall?

IMG_3647No, any tank that is built-in is a wall aquarium.  I just finished my 250 gallon built-in tank.  This tank is 2’ deep so instead of dry walling it in, it makes more sense to have cabinets below and above for the filter, storage and ease of maintenance.  A second wall was opened for viewing from another room.  This adds a focal point to that room and visitors that see this end first are blown away by the depth of the tank.  This was a 8′ closest but makes a much better super tank!

Alternative pets in a Wall Aquarium.

cat_in_aquariumOf course we know that a wall aquarium makes an awesome fish tank but what else can we put in them?  A few ideas come to mind, let’s explore.

How about a shrimp tank?  Shrimps are cool guys to watch as they interact with each other and roam around.  Red cherry shrimps are very popular and grow to around 1”.  A few in a tank can multiply to a hundred in no time at all.  They make a cool freshwater tank colony and are not very demanding so of course they work well in a wall tank.

How about lizards or amphibians?   It would be cool to have a branch with geckos, frogs or turtles inside your wall.  You can have a little pond area in the bottom and a leafy green area above but will it work?  Of course it will.  Just add critters that don’t grow too big for your tank and rig up a heat source.  Be careful not to put heat directly against an acrylic tank or it might melt.   You also might want tape off any holes where they can escape from.

What about an ant farm?  Although I have no experience with ants and don’t know what I’m blogging about I can’t see why not and say, go for it (if it doesn’t work you didn’t get the idea from here).

Perhaps a wall aquarium makes a great tank for your cat or dog… Umm, no.

How hard is it to build a fish tank into your wall?


Quick answer, it’s not hard if you’re handy. Anyone who has experience with drywall and a basic understanding of how a stud wall is built can put a tank into their wall. The only other skill that’s helpful is knowledge of electrical wiring.

First you’re going to cut a hole. You need to know if that’s a load bearing wall or not. If it is you will have to brace it in such a fashion that you transfer the load around the tank. Next you going to finish the stud work and construct a nice flat base for the tank to sit on.

A GFI electrical outlet should be placed in the top corner at this point. If you do not know how to do this you might need to call a friend who does. Then the tank goes in the space, patch up your drywall and trim it out with some wood. Not a hard job if you know what you’re doing.

More detailed instructions:


How awesome is a tank built into your wall?


This is a silly post however, if you are thinking of adding an in wall tank to your house, it’s because they are really cool.  A normal fish tank can look nice and clean but a tank in your wall, one that you see-through between rooms is georgeous!  Guests first response is one of shock and amazement followed by a guess at the cost.  When you tell them that a tank like this costs one-tenth of what they thought and you did all the handywork yourself, they have a new respect for your abilities and think of where they can add one to their home.

Realistic 3d rock wall background


Above is a picture of the background from my tank.  I love the realistic texture of the rocks and the fact that they stick out (some pretty far) into the tank.  There are also caves built into the background that smaller fish can swim through (covered in pic by my giant Oscar).

This background was made with 2″ sheets of white styrafoam insulation, silicone and cement.  First I carved up the styrafoam into rocky shapes and  bonded together with silicone.  I made it in sections so I could put them in the tank after.  Where there are caves I put 2 layers of styrafoam hollowing out the back layer.

Once the styrafoam was sculpted I started to paint/pour cement right on top.  I did 3 layers and I added black and white cement coloring to accent dark and light spots.  I tried to keep it wet with a spray bottle while I was making it so the cement will cure properly.

Then the panels went into the tank.  They were siliconed to the back and I rinsed 3 or 4 times over a week period until my ph levels dropped to a safe level.

It took around 2 weeks to make the background in my spare time and 1 week to rinse but looks awesome, well worth it.  There are a couple spots where the cement has eroded off, I plan on covering these with Java moss.