Introduction: Aquarium Coffee Table

About: I do the corporate IT thing during the day, and diabolical hackery during the night. The Aquarium Coffee Table is my latest hack, but other projects include Car PCs, BEAM robotics, DeLorean restoration

Build an aquarium coffee table for a fraction of the cost of ready-made models, from supplies found mostly at your local superstore. 10 Gallon and 20 Gallon models are easily possible.

Step 1: Gather Supplies

Parts Needed:
20 Gallon Long Tank
24" Fluorescent Fixture (2)
Black Foam Board
Power Strip
Light Timer
1" Chair End Caps (4 pack) (2)
36" x 14" Wire Shelving Unit
Glass Table Top
100W Heater
20G Internal Filter
Glass Vase Marbles / Beads - 12 oz (10)
2 Prong, 3 Way Power Splitter

10 Gallon Alternate Parts:
23"x14" Shelving unit
10 Gallon Standard Tank
1/2" Chair End Caps
18" Fluorescent Fixtures
50W Heater
10G Filter

Tools Needed:
Mallet
Bolt Cutter
Zip Ties

If you have none of the parts already, I've estimated the costs of the 10 Gallon and 20 Gallon models at $115 and $180 respectively. However, this is where an old glass top coffee table, spare wire shelving or extra aquarium equipment can dramatically reduce the cost. Even if you go out and buy every item you need for the project, note that ready-made coffee table aquariums appear to start at $500 before shipping.

Disclaimer: I'm not an engineer, but the shelving used is rated for more weight than what would be added by a full aquarium of the sizes discussed, so I feel quite safe with the choices made for this project. Do read the packaging on the shelving you buy to ensure your structure will support the approximate 10 lbs / gallon guideline.

Step 2: Assemble Bottom Part of Wire Shelving Unit

Either size of wire shelving unit includes 4 posts which usually split in half for smaller packaging. Some of the 36"x14" shelving units have posts which split into un-even lengths, with a top segment roughly 18" tall. This would be the best kind to find, as a short segment like that would provide appropriate legs for your table. If you cannot find such shelves, use of a hacksaw or other implements of destruction will be required.

Add the first shelf at an appropriate height that will allow you to stow your light fixtures and power strip beneath it.

Step 3: Zip-tie Flourescent Fixtures and Power Strip Under the Bottom Shelf

Consider cable routing before securing the zip-ties in place; for example, where is the best place for the power cable to stick out. If using two light fixtures, use the power splitter with your light timer. My arrangement leaves enough clearance for me to unplug the timer and pull it out to change the time settings, as well as plug and unplug the aquarium's filter and heater.

Step 4: Add Aquarium

At this point, put the aquarium in and verify that the heights and clearances are to your liking. I have sufficient space above the edge of my aquarium to reach in and drop food without removing the glass top.

Step 5: Cut the Shelving Wires From Top Shelf, Leaving Only the Sides

Having 2 "shelves" adds stability and good looks to your new coffee table. Using bolt cutters is a quick and easy way to remove the internal shelf area for your top / middle stabilizing shelf. Although I was too impatient, using a dremel or file or other deburring instrument on the remaining stubs from the cut wires would make the upper shelf safer. I recommend doing so if you have human young around who may put their hands on that part of the table.

After placing that shelf, you can complete the support structure by placing rubber chair end caps on the posts.

Step 6: Add in Aquarium Components and Decor

You're almost finished! Test your lights and power situation, and position the table exactly where you'll want it at this point... once you add even 10 gallons of water, moving the table will no longer be easily achieved.

An internal power filter, in a corner of the tank is an unobtrusive, yet highly functional way to provide filtration. Likewise, a standard submersible heater will be needed if you're keeping fish that require a temperature other than that of standing water in room temperature. Route the cables down a corner of the tank, through the bottom shelf and to the power strip. Zip tie in place as needed. Usually, it is highly advised not to power these devices until they are under water, so don't plug them in until you've added water.

I used a suction cup, glass tube thermometer mounted diagonally inside the aquarium so that it would be readable while I sat beside the table.

I used colored, flattened glass marbles as substrate in a very thin layer. Any translucent substrate would work.

As there is not a top directly over the aquarium in my configuration, and I plan to add a species known to jump, I have not filled to the very top, but instead I'm leaving 3-4" of "wall" at the top of the tank. Research your desired species or consider an acrylic or glass inset for the top of the tank. Another option would be to configure your shelf height / post length so that the glass table top would be placed almost directly over aquarium. Leave some space for airflow though!

Step 7: Fill and Add Top Glass

Cut the foam board into appropriately sized strips to wedge them vertically under the bottom shelf in order to conceal the components and the extra light.

You're done! Now you can cycle the aquarium to establish the needed bacteria colony and add fish suitable to your quantity of water.

Due to the arrangement of such an aquarium, a Champagne Island is an ideal addition. I found instructions at this URL:
http://www.petfish.net/articles/Do-It-Yourself/diy-champagne-island.php

I've had mine running for months now, and I must say, it's very enjoyable, and fits perfectly as a unique centerpiece to accompany my atypical end tables and other decor. The only complication I've encountered is that when vacuuming the gravel, the standard siphon effect is pretty weak, given that the bottom of my bucket, resting on the floor, is only about 4" lower than the bottom of the tank. It's still good enough to do the job, but I've considered buying a battery powered tank vac.

Last but not least, I'd like to thank those who posted the Pinball and Stainless coffee table instructables for the inspiration to share my little hack with the world.