DIY aquarium/stand experts please

[kevensquint]

Hi, I had a custom tank built by a veteran tank builder using my specs. The stand is a common DIY type I found on a reef forum using all 2x4's , 6 legs ( 3 per corner, 2 on either side in the center and 5 cross beams under the tank with 1/2" plywood top and bottom. It's over built.
Anyways, 2 questions:
1) how long after the tank is filled can I assume it should be trouble free long term? ( its my first non-brand tank, and I'm lacking confidence).
I won't add the salt and connect everything until I feel it's solid.
2) I my stand has 6x1/2" ceder boards covering the frame which are not straight. They are giving my eyes the idea that my tank has a slight sag in the center. The level sitting on top of all euro bracing says no....is there any other way to see if the center bottom is sagging?

The tank is 60Lx 30Wx 20H , it has a safety factor of 4.2, but likely a bit more because it is euro-braced top/bottom and has a 10" center brace too.

 

[Josh Bayne]

Stand pictures please. I usually do s full framed stand. L 2*4s in each corner and add support around doors and once center brace. But depends how how it's built. We usually tend to over build

 

[Josh Bayne]

I never assumed I would have any trouble after a stand build. If it's anything frame wise 2 that it's s tank.

 

[kevensquint]

The frame

 

[jsker]

1 as long as there is no water damage you should be fine
2 shim any gaps in the uneven boards
3 call insurance company and take out a rider.
4 alway start out a foundation with a plan and you will alway have the confidence that the plan will succeeded . This is a nice way of saying you might get lucky.

 

[Josh Bayne]

Pocket holes to secure to the top frame? Looks good I would also use outdoor waterproof paint and silicon to seal erything inside the stand.

 

[jsker]

The frame

Paint the wood with polyeurthaine and you will be more than fine. Sorry about the spelling

 

[Josh Bayne]

I am not s fan of plywood on rhe bottom, I usually elevate it then add s trim layer in a of watter damage to the plywood I can change it without completely tearing the frame apart.

 

[kevensquint]

I'm afraid I'm not following, I posted a pic of my stand as requested. But there is no issue with the stand. The bottom of the tank when full caused the floor in the center under the tank to sag slightly. Then I imagin the stand and the bottom of the tank as well. I slide a level along the foam base under the tank and the middle shows level, either end has the bubble whithin the black middle marks but show each end slightly higher than the middle. I just emptied the tank. I guess I will shim under the center of the stand.

 

[Josh Bayne]

OK so your top frame sagged, or the entire frame sagged? Or your floor sagged? You will always have some sagging when adding 500+ lbs to s wooden structure. If you wanted to just be safe you can add s removable knee brace in the front behind the doors if you wanted. But I don't completely follow what's going on.

 

[ermartin]

If your level says its straight its straight. is your tank sitting flush on the stand ? by putting in shims where they dont belong you might cause an issue that you don't even really have

 

[Pepcrylic]

If you have euro's top and bottom, and the level shows "NO BELLY" or sag you are good to go. Your stand looks good. Your floor looks good. Its your cedar boards that need to be reworked. Did you ask your tank builder if he will warranty the tank as it sits on your stand? (full of water)

 

[Lenny_S]

OK so your top frame sagged, or the entire frame sagged? Or your floor sagged? You will always have some sagging when adding 500+ lbs to s wooden structure. If you wanted to just be safe you can add s removable knee brace in the front behind the doors if you wanted. But I don't completely follow what's going on.

I say sagging of any kind in the floor or the stand is a very bad thing and should not happen. The dimensions of your tank are almost identical to mine an I've calculated the weight to be around 1800 pounds with tank, canopy, sump, stand, rock, water, etc.. That's a lot in a 60x30 inch area! If you are putting it on your main floor of your house and it's wood frame, even running perpendicular to the joists that area should be reinforced. I have a finished basement so I was able to build a wall 30 inches from the outside wall and carry the load down to the concrete floor.

Stand wise I like 5/4x6 and 5/4x4 construction. And I double up the box framing and cross brace.

I use 1/2 pine panel from HD for the top and bottom. It's lighter than plywood and water doesn't damage it nearly as much

I build one end removable so even a very large sump can be put in and taken out easily.

Here is what it looks like finished (minus the doors)

The kind of stresses and loads are pretty high for a relatively small area. You really need to have a very solid structure all around. Going light may be ok for a year or even a few, but structural failures aren't always quick, sometimes they happen after many years. I'm in the "why chance it" camp!

 

[kevensquint]

After full, the outer sides of the stand are on the floor. There was no gap under the middle of the stand before filling, but once full about a 1/4" gap appears. Showing the entire weight pushed down the floor slightly. Which I believe, caused less, but a still slightly noticeable sag throughout the middle of the stand and possibly the base of the tank itself. I'll take more pics later. Thnks.

 

[kevensquint]

Lenny-S, the tank is in a basement, the floor is as follows. Slab, upright 2x4's, wood floors, 2~1/2" plywood floors then ceramic tiles. The sag is no doubt due to the space between the 2x4 joists under all that. But the floor is extremely solid as a whole and I can't imagine it failing complely. In fact at most it went down 1/4" in the middle, then I believe the stand acting as a bridge sagged a bit causing the middle of my tank to belly out downward. There is no mods I can do to the floor, so I'll shim 1/4" with a large solid piece in the middle under, he stand and refill again to see.

 

[Lenny_S]

Lenny-S, the tank is in a basement, the floor is as follows. Slab, upright 2x4's, wood floors, 2~1/2" plywood floors then ceramic tiles. The sag is no doubt due to the space between the 2x4 joists under all that. But the floor is extremely solid as a whole and I can't imagine it failing complely. In fact at most it went down 1/4" in the middle, then I believe the stand acting as a bridge sagged a bit causing the middle of my tank to belly out downward. There is no mods I can do to the floor, so I'll shim 1/4" with a large solid piece in the middle under, he stand and refill again to see.

Yes. Even just a 1/4" that carries through to the top of the stand puts a lot of stress on the tank.
So this sounds like a wood floor built over the basement slab. It's a shame there is some gap somewhere.
An alternative to shimming the center of the tank I can recommend is to cut out 6 4x4" squares in the floor (1 in each corner and 1 in the middle of each long side) Then place a pressure treated 4x4 in each of those holes where the 6 of them will be about level with the floor, but more importantly level with each other. Then you can line the stand up to those 4x4s so it sits on top of them. Since they will go down to the slab and are pressure treated, you should have many years of worry free support. To finish it up if that creates any gaps between the finished floor and the stand, you can run a toe kick around the stand to cover the gap.
Do you get what I'm saying?

 

[Windy]

With that many holes, why not cut out the floor and see what is wrong. Then after completing repairs you can set the tank over the patch. I would want to know about the sag and maybe what type of lumber was used. How is moisture handled and what utilities are below the floor.

 

[kevensquint]

Not my home, renting. I sagged a previous 3rd floor apt with a 125 and sump by almost 3/4". It blew the ceramic tiles. Which is why now I only chose basement apts.

 

[Lenny_S]

If you can't modify the dwelling then you're left with the stand.
You could frame the top of the stand with doubled up 2x8 micro-lam (glued and nailed together) That would carry the load out to the 4 corners. Over a 60" span that would do it. It's a little expensive, but in the grand scheme of things minor compared to the tank failing.

 

[kevensquint]

Thank you all for your input. My dream tank will likely be moving to my retired parents basement on cement. I'm afraid after removing the ceder panels over the frame, the gap was about 1/2" almost from end to end. When it was flush prior to filling. This in my opinion, is too much sag for one week full. And not worth ending up being sued. I'm really sad after 26 years reefing, this was to be my most high-tech and well thought out reeftank. I can't bare to sell it.