It can cost you as little or as much as you want. Here is the basic blueprints (very detailed sorry if you don't need all the information).

2x4 - White (should be a #1 board to reduce the chance of it not being swisted store assistant should be able to help you pick the right one)
Sheet board - I choose Pine for to cover the front and sides (you can covetr the back if you will be placing away from the wall like center of a room or something)
Trim Base - I choose 1x2 pine for the base trim
Trim Top - for that I choose more pine base board trim
Trim Corners - 90 degree pine

to start measure your tank don't worry about the height just width and depth. My tanks are the following:

12" deep
30" Width

Add half inch to each side for extra wiggle room while the tank is on the stand.

12 1/2 inch depth
30 1/2 inch width

now decide how tall you want the BOTTOM of the fish tank to be off the floor. I choose 4 feet.

48 inches stand height

now the cuts:

4 - 2"x4"x30 1/2" (these server for the top (tank) and bottum (inside floor) shelves

Measure the thickness of the 2x4 standing on edge should be about 1 1/2 each so togeather they are 3 inches. subtrack this from the depth measurement.

4 - 2"x4"x9 1/2"

Take these eight pieces and form 2 boxes.

now cut the floor braces (recommended to better support to have a brace on each corner of the tank and then one ever 2 foot so a 4' tank would have a total of 6 braces)

4 - 2"x4"x48"

Attach the floor braces to the inside corners of each box previously created.

A little over engineered but it's sturday and no worries about it colapsing.

I found these plans by doing a google/bing search for "DIY Aquarium Stand"

hope this all helps.

Quick collage of the aquarium stand build.

The frame completed:


Putting trim and facing on the double door stand:


Double Door and Single Door stands complete:


Double door and Single Door stands complete with Tanks running:

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100G->African Cichlids:Kribensis-2,Bumblebee-2,Red Zebra-2,Elec. Yel. Labi.-2, Acei-2, Elec. Blu. Johanni-2,Peacocks-2 / Community: Australian Rainbow-3,Turquoise Rainbow-4,Dalmatian Mollies-2,white molly-1,Dojo Loaches-1/Cleaners:Chinese Algea Eaters-5/Murderers: Dinosaur Bichir-1And lots of other tanks,2-Gourims,6-Rams,1-Arrowanna,6-FW Flounder,1-Farlowella CF, 1-Spiney Eel

I need to add new picture to this collage. I added in power strips which is mounted to the inside of the stand in the back. I made sure to keep the up off the ground to make sure there would be a drip loop in the cords with out making one.

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100G->African Cichlids:Kribensis-2,Bumblebee-2,Red Zebra-2,Elec. Yel. Labi.-2, Acei-2, Elec. Blu. Johanni-2,Peacocks-2 / Community: Australian Rainbow-3,Turquoise Rainbow-4,Dalmatian Mollies-2,white molly-1,Dojo Loaches-1/Cleaners:Chinese Algea Eaters-5/Murderers: Dinosaur Bichir-1And lots of other tanks,2-Gourims,6-Rams,1-Arrowanna,6-FW Flounder,1-Farlowella CF, 1-Spiney Eel

How big of tanks are these for ?

My plans are for 30"x12" (37 gallon tall, 30 gallon tall), but you can increase the diagram to fit your tank just be sure to inclued the extra 1/2 inch so there is a little wiggle room around the tank on the stand.

for larger tanks you should plan for a floor brace to be installed every 2 feet, so a four foot tank would look like my Double Door Stand. But with that size tank you will want to consider putting a good size piece of base board to help steady the stand.

I wish I was better at drawing blue prints.

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100G->African Cichlids:Kribensis-2,Bumblebee-2,Red Zebra-2,Elec. Yel. Labi.-2, Acei-2, Elec. Blu. Johanni-2,Peacocks-2 / Community: Australian Rainbow-3,Turquoise Rainbow-4,Dalmatian Mollies-2,white molly-1,Dojo Loaches-1/Cleaners:Chinese Algea Eaters-5/Murderers: Dinosaur Bichir-1And lots of other tanks,2-Gourims,6-Rams,1-Arrowanna,6-FW Flounder,1-Farlowella CF, 1-Spiney Eel

Great looking stands!! When you getting the doors on?

I built my own for my 75g. I used 4x4s at my corners and center brace that had notches cutout for a 2x4 rectangle to rest on. Wasn't easy to cut the notches with my tools, but it worked out really well.

I think most people think whatever they build won't be strong enough, but truth is it will probably be stronger than what you can buy. Kind of like building your own computer, you tend to overbuild. I bought a 125g tank and stand and could rest the edge of the stand on my shoulder and stand up with it and walk around by myself. I needed to be helped with the stand I built for my 75. Just to give an idea of what I'm talking about.

Nice job. Post some pics when you get the doors on. I'll be building my own for the 40b I plan to get in a few months.

I do have materials to make the doors. but they wont be anything fancy. :( just don't have all the tools and space needed to really get into it. But hopefully I can work on getting the doors added and latched on by March 5th/6th.

And no worries about the pictures soon as the doors are on I'll get several good views of them inside and out.

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100G->African Cichlids:Kribensis-2,Bumblebee-2,Red Zebra-2,Elec. Yel. Labi.-2, Acei-2, Elec. Blu. Johanni-2,Peacocks-2 / Community: Australian Rainbow-3,Turquoise Rainbow-4,Dalmatian Mollies-2,white molly-1,Dojo Loaches-1/Cleaners:Chinese Algea Eaters-5/Murderers: Dinosaur Bichir-1And lots of other tanks,2-Gourims,6-Rams,1-Arrowanna,6-FW Flounder,1-Farlowella CF, 1-Spiney Eel

Looks good, I like the bath tub style top to the stand.

I just got back from getting my lumber but forgot I wasnt remaking the facing for the 210g's stand and got the wrong sheet of ply. But 8 #1 2x4's (in white) for 1.78 a piece. got a dozen of em, only need 6 for the entire stand.

This new one I am building is for a 50g 3' tank, 2 2x4's at each corner, full frame top and bottom.

Nice White have to post some pictures of the process.

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100G->African Cichlids:Kribensis-2,Bumblebee-2,Red Zebra-2,Elec. Yel. Labi.-2, Acei-2, Elec. Blu. Johanni-2,Peacocks-2 / Community: Australian Rainbow-3,Turquoise Rainbow-4,Dalmatian Mollies-2,white molly-1,Dojo Loaches-1/Cleaners:Chinese Algea Eaters-5/Murderers: Dinosaur Bichir-1And lots of other tanks,2-Gourims,6-Rams,1-Arrowanna,6-FW Flounder,1-Farlowella CF, 1-Spiney Eel

Very nice Stand. How about some Canopy plans to go with them?

Sure I can do that. I've been thinking about modifying the tank stand plans to include a cord/tube guide. Could be something like a painted PVC tube to a metal rod with velcro straps attached to it.

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100G->African Cichlids:Kribensis-2,Bumblebee-2,Red Zebra-2,Elec. Yel. Labi.-2, Acei-2, Elec. Blu. Johanni-2,Peacocks-2 / Community: Australian Rainbow-3,Turquoise Rainbow-4,Dalmatian Mollies-2,white molly-1,Dojo Loaches-1/Cleaners:Chinese Algea Eaters-5/Murderers: Dinosaur Bichir-1And lots of other tanks,2-Gourims,6-Rams,1-Arrowanna,6-FW Flounder,1-Farlowella CF, 1-Spiney Eel

wont see another canopy on any tank I own, I hate those things, they make fish keeping a chore cause you cant do squat with them on.
MEC, check this out
210g discus build - Album - TinyPic - Free Image Hosting, Photo Sharing & Video Hosting
that link is pics to the 210g build, plenty of pics of the stand in there.

MEC, rethink that cable tube on there, you will kick your own butt the minute you have to change out an electrical device(heater ect), I did that now I just use a intake tube that slit from end to end and use a zip tie that has a 3m adhesive pad on the back and a slit for the zip to fit thru.

Awsome, thanks White! Yeah I wouldn't have put anything in place without first checking how easy it was to makes changes. That's why I was also thinking the metal bar with velcro straps to tie the cables/tubes to.

Ok your tank and setup is amazing, I have to get some work done or I would flip through them all.

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100G->African Cichlids:Kribensis-2,Bumblebee-2,Red Zebra-2,Elec. Yel. Labi.-2, Acei-2, Elec. Blu. Johanni-2,Peacocks-2 / Community: Australian Rainbow-3,Turquoise Rainbow-4,Dalmatian Mollies-2,white molly-1,Dojo Loaches-1/Cleaners:Chinese Algea Eaters-5/Murderers: Dinosaur Bichir-1And lots of other tanks,2-Gourims,6-Rams,1-Arrowanna,6-FW Flounder,1-Farlowella CF, 1-Spiney Eel

thats just the build album, there are others.

How tall are your stands again? Im starting to think 30" is gonna be a short stand for a 50 breeder, but then again it brings it down to child height and allows me to still sit on me duff and observe them lol.
Im trying to figure out what/how I want to mount a pair of doors or an access panel somehow, I gotta fit a wet/dry filter under mine and its 27" wide.

My stands are 4 foot to the bottum of the aquarium. For me it's a good height for viewing from both sitting on standing.

The tub finish is just high enough to cover the black plastic on the bottum of the tank so there's no loss of tank viewing.

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100G->African Cichlids:Kribensis-2,Bumblebee-2,Red Zebra-2,Elec. Yel. Labi.-2, Acei-2, Elec. Blu. Johanni-2,Peacocks-2 / Community: Australian Rainbow-3,Turquoise Rainbow-4,Dalmatian Mollies-2,white molly-1,Dojo Loaches-1/Cleaners:Chinese Algea Eaters-5/Murderers: Dinosaur Bichir-1And lots of other tanks,2-Gourims,6-Rams,1-Arrowanna,6-FW Flounder,1-Farlowella CF, 1-Spiney Eel

Did you put some insulation under the tanks? that sheet insulation(usually pink or blue with a silver backing) takes up ANY and ALL imperfections and levels the tank itself a little better(helps with regulating the tank temp too)

Nope no insulation undr the tanks. I originally just put them together to see and well then I was to lazy to empty and refill the tanks for some insulation/padding. For the most part my tanks stay even temps, all through winter/summer.

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100G->African Cichlids:Kribensis-2,Bumblebee-2,Red Zebra-2,Elec. Yel. Labi.-2, Acei-2, Elec. Blu. Johanni-2,Peacocks-2 / Community: Australian Rainbow-3,Turquoise Rainbow-4,Dalmatian Mollies-2,white molly-1,Dojo Loaches-1/Cleaners:Chinese Algea Eaters-5/Murderers: Dinosaur Bichir-1And lots of other tanks,2-Gourims,6-Rams,1-Arrowanna,6-FW Flounder,1-Farlowella CF, 1-Spiney Eel

One thing I see with this design is you are counting on the fasteners to hold the weight. The weight should always be born by the wood not fasteners.

Yeah, but with the piece of ply wood on the top you displace the weight which also rests on the 4 corner 2x4s that run from the floor to the bottum of the ply wood.

To do it over again I would move the inside 2x4s to rest inbetween the top and bottom rectangles. This would make it wood to wood from tank to the floor, and provide more room under the tank for storage.

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100G->African Cichlids:Kribensis-2,Bumblebee-2,Red Zebra-2,Elec. Yel. Labi.-2, Acei-2, Elec. Blu. Johanni-2,Peacocks-2 / Community: Australian Rainbow-3,Turquoise Rainbow-4,Dalmatian Mollies-2,white molly-1,Dojo Loaches-1/Cleaners:Chinese Algea Eaters-5/Murderers: Dinosaur Bichir-1And lots of other tanks,2-Gourims,6-Rams,1-Arrowanna,6-FW Flounder,1-Farlowella CF, 1-Spiney Eel

Try using a half lap joint between the front rail and the leg itself. Then a 2 x 4 filler on the side so it's flush for the plywood skin. I built my workbench like that and it'll hold just about anything. My radial arm saw is built into it and it doesn't move. The bench is 12' long so I can rip a 4 x 8 sheet of plywood by myself.
All that said, your stand is working out for you. You're happy with it. It's holding the weight. That's all that really matters. Even with the way it's built now it's still overbuilt. (That's meant as compliment in a round about manner)