My stand rocks back and forth a bit

[SallyWho]

How do I address this before filling the tank?

 

[Scrubber_steve]

Its either an uneven floor or the stand is a bit askew.
If its the floor, use a shim under the stand.
If the stand is a bit askew it will level out when the tank is filled with water. :)

 

[SallyWho]

Its either an uneven floor or the stand is a bit askew.
If its the floor, use a shim under the stand.
If the stand is a bit askew it will level out when the tank is filled with water. :)

I checked both the floor and the stand- both are level (floor is supported with jacks in the crawlspace). The bottom frame of the stand doesn't move, but the rest of the stand rocks a bit. I think I'm just missing some support or stabilizing thing somewhere. I don't want to risk filling a tank on a stand that moves!

 

[WVNed]

You aren't making sense. Are you saying the top of the stand moves but the bottom doesn't?

Being level doesn't have anything to do with being flat. If it isn't flat on the bottom it will rock. If it rocks back and forth it cant be level in both positions.

Your stand looks plenty strong to me as is and the weight on it will settle it. If it isn't dead flat shim it.

For peace of mind go to Petsmart and look at commercially built stands for large tanks. They are pitiful compared to the DIY ones. I know I have one.

 

[SallyWho]

You aren't making sense. Are you saying the top of the stand moves but the bottom doesn't?

Being level doesn't have anything to do with being flat. If it isn't flat on the bottom it will rock. If it rocks back and forth it cant be level in both positions.

Your stand looks plenty strong to me as is and the weight on it will settle it. If it isn't dead flat shim it.

For peace of mind go to Petsmart and look at commercially built stands for large tanks. They are pitiful compared to the DIY ones. I know I have one.

 

[WVNed]

The stand is designed to carry a load pressing down on it. Not one from the side. It wont do that with the weight on it.

Mine is sitting on carpet. I can slosh the water if I shove on it hard from the side.

Take a pile of bricks and stack them up. You can sway the top of it pushing on it. Now set a house on it and you cant.

You mentioned skinning the stand. Placing plywood on 2 adjacent sides will make it much more rigid. Even if it has cutouts for doors.

 

[TheEngineer]

That is called racking. That’s not safe to put a tank on. Can you get some pictures of how the vertical supports are attached to the top and bottom?

 

[SallyWho]

That is called racking. That’s not safe to put a tank on. Can you get some pictures of how the vertical supports are attached to the top and bottom?

Thank you- I knew there was a name for it! Simple butt joints. On the four corners, the inner board goes all the way from the top to the floor. The outer boards sit on the bottom frame and under the top frame. The four verticals (one in the front, three in the back) sit between the bottom and top frames as well.

 

[TheEngineer]

Nice work. That’s some clean construction.

You can probably fix this with some more screws. It looks like the load bearing legs that go to the floor are screwed into the butt jointed leg it is sistered with, yes? Is that leg also screwed to the leg along the short side?

 

[TheEngineer]

Also, are you planning to skin the outside?

 

[Scrubber_steve]

I see from your 2nd video what you're talking about.
I wouldn't fill a tank on that either.
It needs cross support at the ends to stop the stand >>> wobbling<<<

If you brace sheets of ply on each end of the stand it will be stablised

 

[SallyWho]

Nice work. That’s some clean construction.

You can probably fix this with some more screws. It looks like the load bearing legs that go to the floor are screwed into the butt jointed leg it is sistered with, yes? Is that leg also screwed to the leg along the short side?

Yes, the load bearing legs are screwed into both of the shorter sistered pieces on both sides.

 

[TheEngineer]

In the top picture, the board visible on the right side is actually two, correct? Is that attached to the visible board on the left?

 

[SallyWho]

In the top picture, the board visible on the right side is actually two, correct? Is that attached to the visible board on the left?

Those two outer vertical boards sort of sandwich the load bearing one, and both are screwed to it, but not each other. Think I ought to add a few screws to secure the outer boards together? Will that make a difference to the racking, or do I need to cut some of those triangular/diagonal boards to stick in the upper corners on the sides of the stand?

 

[TheEngineer]

If they’re both attached to the load bearing leg that should have held everything solidly.

Does this only rack in one direction? (Front to back or left to right)

 

[SallyWho]

Sorry, my phone wasn't showing me all the replies so I didn't see these comments, but I'm on my laptop now.

Also, are you planning to skin the outside?

Partially. I can fully skin the far left side, and skin probably the bottom half of the back of the stand, but the right side is going to have my control panel for all the controllers and stuff, and the front is just going to be made pretty- nothing structural. The doors are cut to snap over those holes with magnets.

I see from your 2nd video what you're talking about.
I wouldn't fill a tank on that either.
It needs cross support at the ends to stop the stand >>> wobbling<<<

If you brace sheets of ply on each end of the stand it will be stablised

I see what you mean, thanks! Do you think if I cover the whole left side in a piece of plywood, and the bottom half of the back of the stand (so I can pass plumbing and wires through the gap), that will be sufficient?

 

[SallyWho]

If they’re both attached to the load bearing leg that should have held everything solidly.

Does this only rack in one direction? (Front to back or left to right)

It only racks front-to-back. It's fine side-to-side, thankfully!

 

[TheEngineer]

It only racks front-to-back. It's fine side-to-side, thankfully!

Ok, that’s what I thought. That’s because there are only butt joints holding the tank in that direction. Skinning the left and right sides will fix it.

 

[SallyWho]

Ok, that’s what I thought. That’s because there are only butt joints holding the tank in that direction. Skinning the left and right sides will fix it.

I plan on putting my control panel on the left side. There will be a piece of plywood there, but it won't cover the entire side ( though it will be screwed to the inner edges of that load bearing leg). Will that be okay?

 

[Scrubber_steve]

You can cut holes in the plyboard to pass plumbing & cables through.
I would board both ends fully as per my diagram, & most likely the rear side as well to be on the safe side & peace of mind. :)