Granite table top questions      6/10/14 Dear WWM members, <Devakalpa> Hello from India. You are my favourite website for all water-pet related knowledge and thank you all for doing this awesome job. I have read your archived FAQs, but could not get something that answers my question closely. So here goes: The image shows how I place my 29 gallon (30X15X15) on the top of a table. The dotted lines mark the edges of the top of the table, on which is screwed-in the top surface (shown in yellow). <A very nice graphic> This area measures 36” by 24”. The aquarium actually sits on a 1” thick Styrofoam sheet (not shown). The table is made of 1 inch square tubular hollow steel pipes/columns. The right side has a chest of drawers. The legs have rubber ‘shoes’. The top is made of compressed ply-board, <I would seal, reseal this against moisture> finished with a laminated sheet. It is about 1” thick. The top board measures 44” X 32” and juts out by 4” from the table top frame on each side. <Okay> The ply-board has taken in moisture and is showing signs of stress and waviness. I have supported it from underneath but the water surface is showing a minor angle as it has sagged to the left. <Mmm; not good> I plan to replace the ply-board surface with a similarly sized slab of granite. Is this a feasible plan? <Maybe... I'm concerned with the total weight here... the granite and filled tank is likely going to exceed 500 lb.s> I am concerned about the following: a) Will granite absorb water and lose structural integrity fast (i.e. in a few years) even if I seal it? What is the best sealing material? <There are granite counter top sealants...> b) Is 1” a good thickness and will it sit on the frame on its own weight? <I suspect that you'll have to go with thicker... 1.5, even 2 inch here. Alternatively, I'd put a piece of one inch plus plywood (marine grade if possible) under whatever thinnest granite you can get... use an adhesive twixt these two> b) Since the part of the granite slab under the aquarium will not be supported by anything exactly under it, will it be prone to cracking? <Yes; hence the suggested marine ply> We are looking at probably 130 kg (287ish lbs) over an area of 30X15 sq. inches. <Yes; likely more just with the filled, set up tank> c) Even if I ensure proper leveling, is there a need for a Styrofoam cushion under the aquarium? <Not if using the plywood, granite combination> Thanks a lot. Regards Devakalpa <Welcome. Bob Fenner>

Re: Granite table top questions     6/11/14 Dear Bob, <Big D!> Thank you so much for the very informative reply. I shall proceed as advised. Regards Devakalpa <Cheers, BobF>

How to Calculate Max Weight Limit? Using furniture as an aquarium stand: Not really recommended 4/17/2010
Good day!
<Hi Dennis>
I am hoping to use the ff furniture as an aquarium stand for a 100g tank (72" x 18" x 18"):
http://www.baysidefurnishings.com/products/home-office/BVRD.html (bayside furnishing Bellevue room divider)
<Looks like a nice piece of furniture.>.
I am wondering if there is a way to calculate how much weight it can hold?
<Certainly.>
A completely setup 100g tank will be at least 1000lbs, so that should be the minimum, correct?
<Yes.>
The furniture dimensions are 70" x 18" x 40", the panels are 2.5" thick, and the wood is made of solid ash and ash veneer.
<With those dimensions, the wood itself is more than adequate to support that weight; a properly braced 2 x 4 can support over 1000 pounds......BUT....>
It's not intended as an aquarium stand, but it looks pretty strong and massive compared to some other commercially available stands (but that's probably just my opinion).
<It isn't intended to be a stand or support that much weight. - It isn't so much the wood, as it is the fasteners holding the pieces of wood together.
As the stand is built, the top is supported by the four vertical sections, which are in turn supported by the bottom. With that much weight on the top, the overall structure is very top heavy, Any significant lateral force would likely cause the fasteners to fail. While the wood itself would not break, the end result would still be 100 gallons of water washing through your living room.>
<Further, the stand is 18" wide; with that much weight the stand would be extremely top heavy and unstable.>
I did check with the manufacturer and they said the max weight is 300lbs.
<That sounds about right for most furniture.>
The number just seems too under-rated for the furniture (then again, it wasn't design as a tank stand). I like the contemporary look of the furniture, so I want to ask if this is even feasible?
<I personally wouldn't try it with anything bigger than a 30 gallon tank.>
I could probably setup the tank on the stand in the garage to test it, but if there's a way to calculate it first, that would really help.
<The wood itself would support it just fine, the pieces and parts holding the wood together is another story. Take a look at an aquarium stand there the pieces supporting the tank that are directly in contact between the platform and the floor. This enables the structure to be much more stable with a smaller piece of wood - Leaving the fasteners only really needed to facilitate moving the stand, as once the a full tank is in place, the resulting tension keeps everything in place. - Overly simplified, but somewhat similar to an arch - the keystone keeps everything else in place.>
For the 2" difference in length (1" on each side), I plan to create a base made of wood to compensate for it. I read somewhere here that a 1" thick marine plywood should be good for this purpose. But will the 1" extension on each side be an issue?
<Wouldn't help in this circumstance as spreading the weight across more floor isn't the issue. I do recommend you check around online - there are several stands available that do look like furniture and are designed to support tanks.>
I appreciate any help on this.
<I would suggest doing a Google search for "furniture quality aquarium stands" One site in particular is: http://www.rjaquatics.com/home.html
I've actually seen their work and it is quite good.>
Thanks,
<My pleasure.>
Dennis
<MikeV>

Support for 30 Gal Aquarium (RMF, agree/disagree?)  ~ 01/12/09 I current have a 29 gal tank (30" wide) on a sturdy dresser. I would like to get the extra width of a 30 gal (36" wide), but the top of the dresser is only 32 inches wide. I'm wondering if a 36" sheet of plywood under the tank would be enough support to safely deal with the two inches of overhang that would be on each side? If so, what thickness of plywood do you recommend? thanks, Herm <Hello Herm. To be honest, I don't recommend tanks above 20 gallons be placed on any furniture not designed expressly for the purpose. When I was a teenager, I had a 30 gallon tank that was placed on an oak dresser, and everything seemed fine for months until one night the top finally warped enough that the glass base cracked, and of course all the water came pouring out. Putting the fish into the bathtub saved them, but it sure gave my dad a surprise when he came downstairs in the morning! One Imperial gallon weighs ten pounds, so a 30 gallon tank is going to weight 300 pounds (US gallons are a bit smaller and weigh a bit less, but not enough to make a difference). I surely doubt that any dresser is really designed to support that sort of weight permanently, and certainly not with much of a safety margin. Other folks may have other opinions, but me, I'd recommend against what you're doing. Cheers, Neale.> <<Important to pay heed to what Neale states here... the "average" sort of weight per gallon... There is substantial furniture... that can/will take a good deal of weight... keep a system planar, level... but the majority of desks, tables are NOT strong enough IMO/E. RMF>>

Questionable Tank Stand -- 07/24/07 Hey Crew, Awesome Site!!! Anyway, I just thought I'd ask you guys a quick question. I bought what seemed good at the time: two small, matching nightstand/dressers for my L36" W14" H18" 40g aquarium. I thought these would be good for $20 instead of the $180 stands they sell at my LFS. What I think I might regret about these things is that they don't meet in the middle, and there's about an inch of space between each and that means the tanks not supported about an inch in the middle. I have had this tank for three yrs., and nothing has happened, but I fear something will. Is there too much stress? Should I get a new stand? Any suggestions would be helpful. Thank you, Nate <Hello Nate. Let me tell you a story. One night I was asleep and for some reason I was dreaming about rain. But then I realised I wasn't dreaming about rain, I was listening to rain. And the rain wasn't outside the house, but inside my bedroom. Only after a few moments did it dawn on me that my aquarium was leaking. The bottom pane of glass had cracked during the night because the wooden top of the dresser I had sat it on had finally sagged too far and the pane of glass couldn't support the weight of the water any more. The moral of the story is that you shouldn't assume [a] that any old piece of furniture will support an aquarium safely; or [b] that said furniture will be safe tomorrow because it is working fine today. If you're going to rest an aquarium on two separate cabinets, you have the risk of one of them moving relative to the other, placing stress on the bottom of the tank as one end sags lower than the other. As you probably realise with most aquaria they are very strong in terms of resisting the static forces of a body of water but they are incredibly poor at resisting twisting forces because the silicone has poor resistance to this and the glass has none at all. At the very least, you need to have a single piece of strong wood forming a base upon which the tank rests, plus polystyrene tiles on top of that for cushioning. I'd also recommend some sort of bracing to keep the two cabinets from moving apart from each other. But really, this isn't something I'd consider safe. Your own mileage may vary of course, but I've been stung by the "DIY tank stand" disaster and would never try it again. Cheers, Neale.>

Will the desk hold?   8/24/07 Good morning! How are you? Great site By the way. Tons and tons of info. I recently bought a 20 gallon long. I will be putting on a desk that has held a 5 gallon and an 8 gallon tall (not at the same time). I weigh like 170 pounds and I sat on the desk with the 5 gallon. The desk did not wobble and it was level with all the weight on it. Should I do any more tests or would you say it's okay? One more thing, can I use a pad of carpet as the cushion between the tank and desk? Thanks, -Edward <Hello Edward. Thanks for the kind words about the site. Anyway, in my opinion/experience, the upper limit for putting tanks on anything not designed for supporting one is about 10 gallons. Above that, and you're asking for trouble. While furniture may hold a bigger tank for a while, eventually the wood or whatever sags, and then the stress on the glass bottom of the tank gets skewed, and the tank leaks. Result: poor fishkeeper gets woken at 4 in the morning by the sound of splashing water and has to quickly carry fishes to a bucket and then mop up the floor. Been there, done that, bought the t-shirt. So no, I wouldn't do this. Cheers, Neale.>

Using large buffet as aquarium stand 8/11/05 I am planning on buying a 90 gallon tall tank (36x18x31) or a 70 gallon (36x18x25) and a custom refugium (15x18x31 or 15x18x25) that would sit side-by-side on the same stand.  Would the refugium need to be higher in order to flow back into the tank without a pump? <Yes>   Maybe it can be done at this height if the tank is drilled? <Water seeks its own level...> Anyway, my main question:  The "stand" I am planning on using is an antique buffet.  It is "strong like bull", but I am not sure it could handle the weight of the tanks.   <Mmm, the tanks et al. weigh about ten pounds per gallon filled up... I would at least try placing this much weight on the piece of furniture... to try it out...> Considering the different weights on each end of the stand, would this set up be unstable? <Only way to tell is to try...> Would it be better to get a tank  with a 48" length (centered on the buffet) and forget using the refugium? How do I determine whether this piece of furniture can hold these aquariums? <Experiment... not with the tanks, but equivalent weight> Do the supports need to be a certain distance apart--or certain thickness? <Likely you will want to place some four by pieces of wood every two feet... under the buffet, to support... on the principal members> I would really rather not get another stand if I don't have to.   It will be on carpet on top of slab foundation, and the legs are large and flat. If I decide on the 90 gal, there will be about 180 lbs of LR and 110lbs of substrate.  If I go with the 70, it would include 130 lbs of LR and 110lbs of substrate. <And the water at about 8.2 pounds per gallon... about ten pounds per gallon...> The refugium would hold an extra 30-40 lbs of live rock and 20 lbs of substrate.  The main tank is to be a coral tank and the refugium is to serve as a typical refugium (algae, copepods, shrimp) and a seahorse tank (I am planning to use a breeder box in the refugium to further protect some of the shrimp and pods from the seahorses). Thanks for your time, Angela <Do want to mention that you consider the probable damage to this piece... from moisture, spills... a good, strong stand can be made for not much money... see Ozreef.org for DIY plans here... IMO, leave the buffet for future "Antiques Roadshow" programs. Bob Fenner>