DIY Aquarium stand for 75 gallon.

[Reefer27]

Hi there,



I am in the process of planning an aquarium stand to hold my 75 gallon marine setup. I want to keep it pretty simple, safe and sturdy. The problem I see is having enough room for a sump underneath. The footprint of the tank is the standard 75 gallon at 48 1/2 x 18 1/2 x 21 3/8. The main question is do I use 2x4's or 4x4's?

The problem I am finding is that I need room under the tank for a sump. There will not be ample room to slide the sump in through the sides unless it is undersized and I want at least a 29 gallon sump.

If I were to build without cross braces I could easily put the sump in through the front. Is it safe to build a stand without cross braces? I could put one on the back but for full access up front I would like to avoid one. Above all though, I need the stand to be secure and safe and the cross brace seems fairly critical to me but I am no engineer. I have attached a few plans and pictures for stands similar to what I am thinking.


DIY aquarium stand lots of photos - first ever woodworking project - DIY Aquarium Projects - Aquatic Plant Central

Reef Central Online Community - DIY Stands Template and Calculator

Any advice, recommendations or plans would be greatly appreciated.

[FONT=&quot]Thanks[/FONT]

 

[jim692]

I like the reef central template you have posted.
Very sturdy design.

 

[jsoong]

If you do the joints properly at the corners , you can do without cross braces.

I like the Reef Central design as well. The L - shaped legs will go a long way towards preventing racking <which is what the cross bracing is for.> If you can, join all the corners using half-lap & bridle joints. This will be far stronger than the butt joints shown. <A half lap joint has sheer strength of ~1600 lb, butt joint only around 600 lb.> The Reef central design, however, compensated by having the green corner pieces, so it will likely be strong enough.

In any case, do all the joints with cabinet grade wood glue, reinforced with screws. <Titebond III is the top rated water resistant glue according to my woodworking mag.>

FWIW, I built my stand using L - shaped legs, jointed to the rails using half laps. I have the stand completely open front & back, with no structural cross bracing on any sides. It had been totally rock solid.

 

[Egress]

Good info above, just one addition. Assuming you will be using cheap dimensional lumber, use 2x6 for your rails. This will allow you to leave out a vertical brace on the forward rail, a 2x4 in the same situation would probably deflect.

 

[Reefer27]

Thanks for the reply Egress. Jim had also suggested using a 2x6 for the upper rails. Does this not mean the entire top rails will be 2x6? This would include the yellow end pieces. Is this correct?

Also would you guys suggest a vertical brace on the back rail? If so what size? If I don't need it I won't bother. By the sounds of it this is a pretty sturdy setup.

What do you think of using steel angle brackets to brace the bottom frame? Just four 90 degree brackets...one in each corner??

If I do go with 2x6's for the upper rails, do I change the size of the upper blue piece r just stick with 2x4's? I was going to have three of these pieces along instead of one. There doesn't seem to be any load on this so it probably doesn't matter.

I was going to add some to the bottom also, this way I will have a nice support for the sump and stuff.

All suggestions are welcome.

Thanks

 

[jsoong]

Yes, you would use 2x6's for the entire perimeter at the top. The middle blue pieces, you can use 2x6 or 2x4. I used small size for the cross pieces. Reason is that a glass tank is supported only at the perimeters, so those rails are just there to keep the top square & are non-structural. Using smaller size gives you an extra inch or 2 for your equipment inside the cabinet. <OTOH, if you have an acrylic tank, the weight is distributed to the entire bottom, not just the rims .... you would want to have beefed up middle as well.>

If you use 2x6's for the rails, you can dispense with the central support for the rails. You can put one in for peace of mind tho.

You can use angle braces to simplify your joinery. Although I would use braces for decks, rather than flimsy joist hangers or the cheap 2/3" braces in the plastic packs. Those braces are pricey, so I opted to do wood joinery instead.

 

[Reefer27]

Hey thanks Jsoong.

Do you have any pics? I am looking for some shots of how to assemble the initial frame. Top and bottom essentially. With clamps or a square or anyway that will give me a perfect 90 degree connection. I know it seems so simple but I can't picture how the clamps would be setup.

I also intend on using carpenters wood glue. Do you add the glue, clamp and let set...then put the screws in?

 

[jsoong]

This is my original construction thread, it is about 6 years old:

http://www.aquariumadvice.com/forum...-stand-work-in-progress-finished-22450-3.html

To align the frame, the method depends on your joinery. With half-laps, the joint itself will align to 90 degree if cut accurately. If you are doing butt joint, then you will need either a jig or long clamps.

Assuming butt joints, what I would do is glue & screw down all 4 corners of the frame. Make sure your pieces are accurately cut to size & lined up perfectly. <Don't wait for the glue to set, the screws will act as your clamps.> With the glue still "workable" (about 20 min), you want to align the frame to 90.

You can do this by either building a 90 degree jig - a perfect 90 degree piece of plywood with attached rails - you clamp the jig to the corners to force the joint to 90 degree (you need at least 2 of those kitty corner, 4 even better.) You let the whole thing sit overnight for the glue to harden & the frame should be nicely squared.

Alternatively, you can measure the diagonals of the frame. These should be exactly identical. You adjust the frame to this by putting 2 long clamps on the diagonal & at least 2 other clamps across the carcass. You skew the clamps to obtain a perfect alignment. Once the frame is aligned, you put in the center bracing (blue pieces) to lock things in place. Again, leave the whole assembly overnight so the glue is set & the alignment is locked.

 

[meegosh]

I used the reef central stand plan and I am completely satisfied with it. I used it for my 30g long and put my 10g under it. I posted a build thread on here a while ago. I used 2x6's at the bottom so my 10g would be higher up off the ground. Other than that I followed the RC plan.

my thread:
http://www.aquariumadvice.com/forums/f20/30g-long-and-10g-stand-102727.html

 

[Reefer27]

Thanks so much Tsoong. I am doing butt joints so if I made up a few of those jigs it will be easy. This is really going to help.

I have a question about the next step, you said, :

"Assuming butt joints, what I would do is glue & screw down all 4 corners of the frame. Make sure your pieces are accurately cut to size & lined up perfectly. <Don't wait for the glue to set, the screws will act as your clamps.> With the glue still "workable" (about 20 min), you want to align the frame to 90."

Will the frame move much with the screw in it? I thought once the screws went in it would be tough to move.

 

[jsoong]

The joints will still move a bit until the glue set. With the pieces cut square, you should be pretty close to square once you tighten the screws. You cna usually move things 1/4 to 1/2" until the glue sets.

 

[Reefer27]

Awesome. Thanks.

 

[Reefer27]

What type of glue?

 

[jsoong]

I use cabinet maker's glue. the open time is 20 minutes .... that is how much time you have to work with it until it sets.