Fish Tank Weight and Reinforcing the Floor?

Dazmguk

New member
I'm not sure if this is the right place to post this, but I'm new to the hobby and the forum, so here goes. I have a 75 gallon tank and I'm think of upgrading to a 150 gallon or a little more and then using my current DT for a sump. This of course is going to be a considerable amount of weight, to put on a floor, with a basement underneath?
To offset some, I was thinking of putting the sump in the basement, directly underneath. The tank would be pretty much against an outside wall and very close to the corner of another outside wall. However the load bearing beams underneath would run in the same direction as the tank, so the load would only be distributed over say two or three, instead of more if it was turned the other way (I can't do that, because of the windows). So, my mind went to bracing the beams and floor somehow? Its an unfinished basement, so that's not a problem, however a great cost would be. Of course not as much as 150 gallons of water, rock and sand, not to mention livestock, falling through the ceiling. Any thoughts? Am I being over cautious?
Thanks.
 
That is a lot of weight and as you mentioned would likely be better running perpendicular to the floor joist.

I doubt anything would crash through the floor but perhaps potentially crack the tank if it were to become unlevel due to the weight.

For piece of mind and a cheap solution if the ceiling downstairs is unfinished you can cut a couple 4x4s and use them as support beams from floor to supports under the tank area.
 
I'd look at doing something if you're going to put that much weight in one place. You're looking at close to 2K lbs when you have a finished product. I wouldn't chance it.
 
Well, I'm not an expert, so you'll have to make due with my educated guess (at least until someone else answers)

I know that there are calculations out there on how much weight your support beams can handle, but it has a lot of factors.
Size of the beams, span of the supports and so on

If I were you, I'de just strenghten it anyway ( if only to make me sleep at night)

I would make a frame with the same dimensions as your tank and fix it to the support beams, and on every corner a beam to the floor...... better safe than sorry I would say

2X4's would suffice IMO

Hope it helps

Ivan
 
Thinking and then asking about it is definitely not being over cautious, even if the end result is that you don't need to worry about it.

The general consensus seems to be that putting your sump in the basement is just straight out the best way to go, if you can.

And really, if you're seriously concerned about the weight - bring in a structural engineer to to a site survey. It may cost you a few hundred dollars, but they'll be able to give you a much better answer than can be given over the internet. Though I'm sure there are people here that can give you a rough idea with a bit more information (size of the floor beams, their horizontal span, etc).
 
IME...In most cases 150g tank should not be a problem, I would definately put sump in basement, if you can. If you want, the best way to 'beef-up' your floor joists would be to 'sister' another beam to 1 or 2 of the joists that your tank will be over. (this can eventually be hidden in the ceiling)...
if it doesn't matter to you, the other solution is to add some additional support columns, which are easy to install.
 
All my sumps are in the basement. However my tanks are about 3500 lbs each so I did reinforce the floor. Cannot hurt to be overly careful.
 
I'm not sure if this is the right place to post this, but I'm new to the hobby and the forum, so here goes. I have a 75 gallon tank and I'm think of upgrading to a 150 gallon or a little more and then using my current DT for a sump. This of course is going to be a considerable amount of weight, to put on a floor, with a basement underneath?
To offset some, I was thinking of putting the sump in the basement, directly underneath. The tank would be pretty much against an outside wall and very close to the corner of another outside wall. However the load bearing beams underneath would run in the same direction as the tank, so the load would only be distributed over say two or three, instead of more if it was turned the other way (I can't do that, because of the windows). So, my mind went to bracing the beams and floor somehow? Its an unfinished basement, so that's not a problem, however a great cost would be. Of course not as much as 150 gallons of water, rock and sand, not to mention livestock, falling through the ceiling. Any thoughts? Am I being over cautious?
Thanks.

What is the dimension of the floor joist?
What is the thickness of the plywood/planks?
What is the distance from the wall to the closest joist?
What are you basement walls constructed of?

Shoring of the floor is not a big cost and can be done simply w/ a post attached to the floor joist under the location of the tank...the floor won't fall under the weight of a tank that size but you could get a minor amount of sag (1/4")....

Think about it this way...even though you are not spreading the weight across all the joist if they were running perpendicular you do still have plywood or 3/4" planks(running diagonal) that helps spread the load....
 
Cannot hurt to be overly careful.
+100%

I like izzy123s idea about framing it would also then give you the perfect spot for your sump/ pipes
I have had a structural engineer to my home twice in the past, once for a 300g DT, and 3 yrs ago for my 450g DT...not even for the 450g did he suggest 4 columns, underneath the tank
I realize that every situation/home is different, but I would think that in most cases a 150g is not a problem, but if you're worried...1 (or 2) steel/adjustable lally columns with a 4x4 header (from Home Depot) should be more than enough. Would take 'no' time to install!
 
You could even do a single lally column with a 10" header centered on it, since it is only affecting 2 or maybe 3 joists. 2 would be easier though, you could reinforce the floor for way beyond what that tank weighs for about $100.

You could do it for about $10 if you go with Izzys idea, which will give you far more support than you would ever need. You could build 2 small frames, one on the end of where the tank will be above, and one in the center. Overkill, but if you have the room for it, it cant hurt.
 
You could even use the support beams for a sort of shelf, you need the room anyway for all the "stuff" you have gathered already........ and let's be honest, we accumulate a lot of things........ extra tanks, skimmers, pumps, lights,.......

It's the same for all reefers I think...... haha

By the way, let us see some pics once your up and running.......

Ivan
 
Go to a home improvement store and buy a jack post (they can support like 10,000 lbs+)and a 4x4. Just put it in place under where the tank will be. Should easily support the weight.
 
It is always good to add support but I have seen tanks in the middle of a house setting on one joist for years even one that's a 180. If you don't mind that you have to tell people not to jump up and down in front of the tank that is. One tank moves at least two inches if you bounce a little. Tanks in apartments are like this a lot. I am one of them. :p the weight is spread out and not pushing down in a single spot. I wonder how many tanks fall through the floor. I have seen tanks leak, crack, blow out and one catch on fire, one guy almost killed himself after sticking his finger in a 400w MH socket (This was bad) but never a tank falling through the floor. Still if you can I would add a Lally Column or two, if only to prevent the bouncing. Just in case you have a dance floor in front of the tank or rowdy kids.
 
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haha! I love these kind of questions!
I had a 150 running parallel for some months, and on the same joists on the other end of the wall I had a 72 w/ sump. Didn't even think twice about floor structure... that is until I came across a 265 gallon tank
After literally months of talking to people on forums getting mostly opinion statements, I realized I was going to get 50% of people say yeah its fine, and 50% of people say no way. The issue is, we can't say by experience truly what your floor can withhold. We don't know how old your floor is and if it is showing stress and so on and so forth...
Your best bet is to contact a structural engineer in your area and see what he has to say, or maybe even get him to swing by one day after work if hes a nice guy like mine was.
Oh yeah, did I mention I had the 265 in a SECOND story apartment??? hahaha Sooo I can't really tell you it'll be fine. But main floors are always built stronger.

It will also depend on the year of the building, if built before 2004 it was constructed by 2x10's every sixteen inches. Anything after that 2x12's every 12 inches. According to most building code.


Here's some links to help you out with placement, and floor joists weight loads.

http://badmanstropicalfish.com/articles/article28.html
 
The simplest and cheapest solution is to add a single lolly column/floor jack. They're called different things in different parts of the country. About $75 at your local big box hardware store. Install that and you should have no worries. They are usually load rated in the thousands of pounds. The only down side is that they take up space in the basement and may interfere with where you put your sump and other equipment, or otherwise intefere with your movement down there.

I currently have a 150g tank on my main floor. Joists run parallel with the tank just like yours. My floor joists are engineered wood I-beams, which are stronger than solid wood floor joists, and my span is only about 7 feet. When I built the house I even doubled up a joist (i.e. added an additional joist) under the tank. The tank sits in a corner of the house right near both foundation walls. I STILL had about 1/4 inch of sagging.

Since my 260g tank arrives next month, I ran the numbers (my dad is a very good mechanical engineer, and I used to be an engineer) and discovered that I was beyond the safety margin for load. So I had contractors install 2 steel I-beams parallel to the joists and under where my tank will sit. One end of each I-beam sits on the foundation, and the other end sits on another steel I-beam which has about a 12 foot span from foundation point to foundation point. You could park a car on that spot of my floor without problems, and coincidentally, that's roughly what my new tank will weigh. Yeah, it cost me a bit but I'm going to sleep much better at night. If your basement isn't finished (mine is) it wouldn't be too hard to do it yourself.

Let me put it this way, how much would it cost to replace your tank, fish, corals, etc, clean up waterdamage from 150g of saltwater on your main floor and basement, take vacation from work to deal with it, have a stressed wife, your stress? Do you really want to risk this?
 
my 150 happens to be over a crawl space on the addition we put on our house. Our floor is 24 feet long and the tank had to go parallel. I ended up getting 3 of the 32 inch column jacks at HD, placed 4x4's with enough length to support 2-3 joists, and put them right under where the tank sits. I know it is way overkill but for a total of like $80 or so it was worth the piece of mind.
 
I'd look at doing something if you're going to put that much weight in one place. You're looking at close to 2K lbs when you have a finished product. I wouldn't chance it.

Depending on how the tank is contacting the floor, the weight could be from 16 LBS\SQ ft if the whole bottom is supported by the floor to around 45 LBS\SQ Ft if you are using a retangular support frame 5 feet by 2.5 Ft and 4 in width beam with one middle cross base. Most building codes require a normal 12 " support beam floor to hold 40 LBS\Sq Ft live load and 10 LBS\Sq Ft dead load.
Even though the total weight is around 2 K does not mean that every point of the the floor will see this weight.
Some one wearing high heel shoes will put more weight on the floor than this tank unless it is using the shoes for its support.
 
First tank not on a concrete slab

First tank not on a concrete slab

I am looking st starting my first saltwater tank. I really want 120-150 gallon tank. My question is that I have 2x8 floor joists 12 inches on center. I have 3/4 inch plywood for my sub floor and the weight is within 12-18 inches of a load bearing wall. If I get a 6 foot tank I would be on at least 5 joists holding a bunch of weight. How concerned should I be about the floor failing. Or would I be ok? Any help would be great.
 
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