Do I need to reinforce the floor?

[wolf_bluejay]

Originally Posted by Gripenfelter

7 foot 200 gallon tank with stand will weigh about 2500 lbs.

It will sit length wise on 2 floor joists that are 16" apart.

The tank will sit perpendicular to an exterior wall.

Joists are wooden I-beams and sitting in the concrete wall on one side and the other side is sitting on a steel beam.

Joists are 15 feet long between the concrete wall and steel I beam.

Do I need to reinforce the floor or will I be ok?

House built in 2009.

Just looking at the numbers, and I'm somewhat guessing because you don't specify the height of the wood I-beams.
This is a bad, very bad idea without reinforcement.
I doubt the floor would fail, but the flex in the floor from the weight would probably cause the tank to break. A 15' span is pretty big, and with a 7' tank you are going right to the middle of it. And to give you an idea, if you have a "larger" friend, say 300' or so, get him to stand where the corner of the tank would go, and put a glass of water on the floor nearby. And now stand back and get him to jump up and down. Not hard, just bounce repeatedly. You will see the "flex" in the floor.

As well, a 200 gal will weigh in much more than 2500 lbs and closer to 4000 lbs with sump, glass, rock stand and other equipment.
For comparison -- my 220 gal is perpendicular to my joists, with the back side of the 6' tank resting directly above a concrete wall. The joist span if only 8.5'.
I added a closet below the tank on one side, so the span is really only 6' and I added extra joists so that the tank was on 7 instead of 2. I glued and screwed the extra joists to the existing, and beefed up the main beams they rested on. The tank is not on a regular stand, but rather a 3' "wall" build with larger lumber.
I really overbuilt the support, but it cost me a total of $100 to sleep at night. and even after all this, the floor deflected still by about 1/32" when the tank was filled.

So, do you want a tank that moves, shakes and slops all over the place when someone walks past it. Or do you want a tank that doesn't scare the crap out of the kids if you jump on the floor in the room?

Honestly, support the tank. I had a 90 gal before my 220, and it moved a bit as you bounced on the floor while working on it. With the new one, I could have a party beside the tank and feel comfortable.

Just build a closet at the around the tank below (you might have to do a little concrete work as well).

[lastlight]

Great advice there! Our floors will hold whatever we place on them realistically but it's how they hold them. My 225 had poured footings, massive LVL behind and jackposts in front. You could jump as much as you wanted without much more then the SLIGHTEST of a little ripple on the surface.

My 34g Solana bounced around my livingroom like crazy so I even tossed a jackpost under it (still under my 97g). If you have access underneath use it!

[Gripenfelter]

I guess I should mention I have granite and marble tile flooring.

So the joists are about 12" in height.

On top of that there is plywood. On top of plywood there is a few millimetres of concrete, then a steel wire mesh, 2-3 mm more concrete, then a 12-14 mm thick granite or marble tile.

Originally Posted by Myka

I come from a carpentry background. I wouldn't do this. What is the floor like on the level below? Dirt? Concrete?

Here's the options I would use:

1. Turn the tank the other way to go across several joists.

2. Reinforce the floor with several short beams running perpendicular to the tank under the current floor joists with adjustable steel jack posts holding them up (don't forget to secure the tops and bottoms of the posts). This would be really easy to remove in the future should you move or take the tank down. However, you need a good base to set the jack posts on.

Basement is concrete. Floor is a floating concrete pad. I was told not to put a telepost there because it would shatter the concrete where it stood.

I can jump up and down all I want around my 120 tank and barely a ripple in the water. I had throught about joining the bottom of the joists together with 2x4s. Hmm.

[Myka]

Originally Posted by Gripenfelter

I guess I should mention I have granite and marble tile flooring.

So the joists are about 12" in height.

On top of that there is plywood. On top of plywood there is a few millimetres of concrete, then a steel wire mesh, 2-3 mm more concrete, then a 12-14 mm thick granite or marble tile.

Basement is concrete. Floor is a floating concrete pad. I was told not to put a telepost there because it would shatter the concrete where it stood.

I can jump up and down all I want around my 120 tank and barely a ripple in the water. I had throught about joining the bottom of the joists together with 2x4s. Hmm.

You're going to crack the tiles and/or dislodge them or the grout if you put that big tank on there without a lot of reinforcement.

Whoever told you that you will crack the concrete below was probably right (it won't "shatter" though). Do you know how thick it is? You would probably have to cut out a similar shape to your tank (except bigger each direction), and dig out the dirt below to pour a thick footing to put the jack posts on. Depends how badly you want to put the tank there I suppose!

[Gripenfelter]

Originally Posted by Myka

You're going to crack the tiles and/or dislodge them or the grout if you put that big tank on there without a lot of reinforcement.

Whoever told you that you will crack the concrete below was probably right (it won't "shatter" though). Do you know how thick it is? You would probably have to cut out a similar shape to your tank (except bigger each direction), and dig out the dirt below to pour a thick footing to put the jack posts on. Depends how badly you want to put the tank there I suppose!

My home builder told me it would crack. Sorry I said shatter. He said crack.

The concrete floor in the basement is 5" thick I believe. The house sits on 24 concrete piles with the exterior walls and centre steel post resting on the piles.

[Myka]

I'm not familiar with prairie building codes (my carpentry experience was in BC), why is your house on piles? I'm assuming you're calling it a basement because it is a living space under the tank, right? With a living space below it could be quite the eyesore to reinforce the floor. Why don't you just get your home builder to come in and suggest a way to reinforce the floor?

Personally, I would just figure out a different way to position the tank.

[Gripenfelter]

Originally Posted by Myka

I'm not familiar with prairie building codes (my carpentry experience was in BC), why is your house on piles? I'm assuming you're calling it a basement because it is a living space under the tank, right? With a living space below it could be quite the eyesore to reinforce the floor. Why don't you just get your home builder to come in and suggest a way to reinforce the floor?

Personally, I would just figure out a different way to position the tank.

Home builder suggested slipping in another floor joist and connecting the bottoms of the joists together with 8 foot 2x4s or one steel beam.

Just curious if anyone else had any better ideas.

Wish I had my blue prints handy. Reinforcing the joists will not be an eye sore because it will be behind a suspended ceiling.

Gonna put the sump in the basement.