Help deciding on a tank

[Areseebee]

I am planning to buy a large tank for my living room but I've been going back and forth non-stop debating. I have lots of space (easily 7 feet long and 3 feet wide) that is not limiting for me but it's on the main floor with an open basement beneath it. The basement ceiling below is finished so I don't have easy access to add support. Importantly, I'm going to try to plumb the sump/ATO in the room next door which previously held a washing machine, so that weight will not be on the joists supporting the tank. For reference about the tank placement, it will run perpendicular to the joists near a wall. I BELIEVE the foundation actually runs 5-6 inches past the exterior wall and under the living room (the basement room below is shorter than the living room by ~8-9 inches). So I think at least part of the tank will be sitting directly on the foundation/basement wall.

To give an idea of approximately where I'm at, my main thoughts as of now have been between the IM 150 and something 6 foot and thinner like maybe the waterbox 230.6. I really like width in a tank and don't care much for height above 20 or so inches (I know the waterbox is a little taller). The fish I'd like to be able to include that are space limited are the long nose butterflies (CBB, yellow longnose, etc) and a regal angelfish otherwise I mostly like smaller fish like wrasses.

I'm at a bit of a standstill because I haven't been able to find a structural engineer that is interested in just coming and advising, I do have a contractor coming to finish the other half of the basement so maybe I could have him pull down the finished ceiling and add support, but I'd like to avoid a huge expense if possible. Overall I'm just curious if anyone has wisdom about what my best options and how to proceed.

 

[littlefoxx]

Following, Im wondering the same

 

[Jekyl]

How many joists will the tank cross? What type of flooring will the tank sit on?

Fwiw my 90g sits in the middle of my house, running parallel on 1 joist, while sitting on top of hardwood floor. This amount of support has held for over 5 years without issue.

 

[Areseebee]

Ooh important information I forgot. So the joists in the rest of the basement are 1.5 by 11 and they are spaced 16 inches center to center. so a 48 inch tank will span at most 3 and at worst 2. A 72 inch tank is likely to span 4 pretty much no matter where I put it.

 

[Jekyl]

Ooh important information I forgot. So the joists in the rest of the basement are 1.5 by 11 and they are spaced 16 inches center to center. so a 48 inch tank will span at most 3 and at worst 2. A 72 inch tank is likely to span 4 pretty much no matter where I put it.

That's generally the only thing people look for, is how many joists the tank will cross. I'm no engineer, however I also don't think this will pose any issue.

 

[TheWoos]

Likewise not an engineer but do have one coming on Monday to look at my second floor apartment to provide me with a psf load on certain places around the unit.

There are two things i have learnt so far about "dead load" capacity:

1. The height of the tank essentially determines the pounds per square foot of the tank since the Length and Width changes expand the footprint of the load spread. There are other elements such as materials of the stand, glass thickness e.t.c but the height of the tank with water alters the PSF since it increases the weight over the same surface area. The shallower the tank the safer the load.
2. Placing the tank against/near load bearing walls is the safest course of action if you cant get an engineer out, walls framing your house with gutter edge are 99.9% likely load bearing since they are holding the roof up.

Hope it helps.

Edit: What about getting a Structural Engineer to at least give a factetime consult, may be able to give you better information and wont cost as much as getting one out to your house. You could do measurements for him over the phone and he could give you "best" advice

 

[Areseebee]

Yeah good points. Where did you find a structural engineer? Old threads suggested I call lumber yards but any I called either didn't have one or thought I was crazy for thinking they would.

 

[Gill the 3rd]

You should be fine. You are conservatively looking at 3000 lbs spread over 4 to 5 2x12 joists, also partially resting on your foundation wall. Your subfloor will potentially spread the load out to other joists as well depending on the layout. This is the ideal scenario (other than being directly on concrete) and I personally wouldn't hesitate to do it. I'm not a licensed structural engineer, but I am a licensed mechanical engineer (also framed houses in a previous life) who works directly with structural engineers so I know enough to be dangerous.

If you are still concerned, sketch out your floor joist layout and the proposed tank location. Give them the joist sizes and proposed tank weight and they can tell you pretty quickly if it works or not.