Aquarium Stand, am I asking for trouble?

[Dave Mc]

Since we moved 10 years ago, my 220 gallon aquarium has been taking up space unused. I've decided it's time to set it back up.
But before  I do I need to make a new stand. The old one is decidedly shaky. Dimensions are about 72"x24"x30" The weight it needs to support, I can only guess, is substantial.

Since this is a mixed species salt water tank I would like to stay away from metal fasteners and plywood. Instead I hope to rely on joinery (rabbit, mortise and tenon), inlay keys and glue. (if possible)

Or should I just hide stainless screws (pocket)?

The doors to access the equipment will probably be just sliding. Overall I am shooting for a Moroccan look. Something along the lines of this desk:


Any suggestions?

[®smpr_fi_mac®]

3/4" ply will be plenty strong. Don't avoid it out of fear of it not being able to support the weight.

220x8=1760lbs and that's *just* the weight of water. The weight of the stone displacing the water will be greater, so you're looking at at least a ton.

Will your floor support that?

Of course, M&T is your strongest joint and will work great.

Do you have Sketchup? You can start drawing it there, post pics here, and get advice as you go along.

[mr_skittle]

That is A LOT of weight. Seems like enough to make a floor sag if its put in the wrong place.

[TomFromStLouis]

Yes, you are asking for trouble. I speak from experience. This might be my most emabarassing woodworking confession:

I made a stand for my 220g tank with apparently two flawed designs since I had two seam leaks in 5 years. 200 gallon leaks can be inconvenient. I now have a 180 on an ugly factory made stand. 

Here is what I learned. Do not rely on a flat plywood surface under the tank. This worked for years for my 75g tank but I think a small amount of water spilled on the ply lifted one corner of the bigger tank, torqued the bottom, and caused my leaks. Look at aquarium store stands (if you can stand the ugliness), they only support the edges. In fact I am told the tank really only needs support at the four corners and of course they need to remain in one plane. If your design can accomplish this then you are in business. I recommend you not veer too far from the proven designs you see in the store for the functional support bits. So, maybe start with a 6x2 rectangle of 2x4s on edge and support them from below in a way to assure they stay in one flat plane. Obviously install it dead level and minimize the amount of wood contacting the carpeting since you will want air flow to dry out spills.

[Steve N]

Off the top of my head I'd say a torsion box of 3/4" ply with 6" spacing will hold the weight, and if made well is dead flat. Problem is, you generally make them no more than a foot tall. I have no experience in stacking them atop one another. If you could, you could then do a surround any style you liked.

[jteneyck]

Tom has it right; you don't want a flat bottom, you only need/want support along the edges of the bottom of the tank.  If you have a flat bottom and any water gets down there it will swell and cause uneven support around the edges and result in a real leak. 

The key issue with designing a stand is not supporting the vertical load, it's preventing wracking.   I would make a mortise and loose tenon frame with at least one intermediate leg, with plywood panels in the frame openings on the sides and back, and put the cabinet doors/drawers between the front frame members.  Conceptually like this 40" wide cabinet, but with an intermediate leg. 



John

[nodima]

Two keys for aquarium stands are to ensure the verticals go from the tank rim down to the floor, giving solid support directly to the tank combined with a flat plane on the top.  One clarification - acrylic tanks require a full flat surface as they have no rims, but glass tanks with rims only need support at their perimeter.   Either way, ensure the top is a single plane.

From experience - plan the stand to ensure that you will be able to maintain the equipment under it by ensuring sufficient vertical space over your tallest equipment, and be sure the door openings are wide enough to fit the equipment.  I missed measured a sump once, and had to break down a 125 to get the sump in place.  The only way it fit was through the top of the stand.

Built a stand for a 180 using 2x verticals and horizontals, with plywood backing for reducing racking, then added a face frame of oak 



To ensure space for the sump, I did not add a 3rd vertical on the front right side of the stand, but did on the rear.




Also, for a 200, you are looking at at least a ton, do not install that with carpet underneath the stand.  Concrete floors would be the best, but if you have to put it up in the house, be sure you do your homework and span as many joists as possible to distribute the load.

[measure once cut remeasure]

I would use microlams for the framework, after all they are designed for loads. The 18+/- layer plywood has an exterior grade glue just in case it gets wet.

Depending on the floor leveling feet might be an option.

[Hank Knight]

A gallon of water weighs 8.34 lbs. The water in a 200 gallon aquarium weighs 1,668 lbs. Plus whatever the aquarium and apparatus weigh. Oh, and the fish, of course.

[Dave Mc]

After seeing this picture, perhaps I am over thinking the engineering.