Moving, need to plan for my 950g

prickles

Premium Member
Hello all, I'm moving and ordered a new 950 gallon tank. My current 1400g won't fit in the new house :(

Last time I cut out the slab and poured more. Do I need to do that or not?

It will be 36 sqft and about 950 gallons. Will a standard 4" slab support that or should I cut it out and pour a deeper slab in that area?

thanks in advance!
 
I'm not a structural engineer so take this for what it is (opinion).
Hard to say exactly without knowing the specs of your particular floor, but, I think the average slab pour is done to ~ 3,000-3,500 psi. Now for the other part.
What is under the concrete? If its granite then you can put just about anything on it.
If part of the year its full of water and then drys out swelling can occur. Maybe a mix of sand, rock, clay, ect... example:

_________________________________
XXXXXX..................XXXXXXXXXXXXXXX

Where "X" is rock and "." is sand. If you put a heavy object over the sand the concrete will crack depending on how heavy the object is and how far away it is from the nearest X. Engineers call it a "cantilever".

Its a guess. If it was me I would dig out what there and drill some support footings. Maybe you could even sink the floor a bit and put in a drain under the tank to catch water that might find its way out of the tank.
 
The old one is about 11.5' by 52" deep by 48" high . The new one 9' by 48" deep by 42" high. So basically similar just a bit smaller in every dimension. Both age tanks. 3/4 starfire with pvc bottom and steel frame at top and bottom.

Oh and probably a 400 or so gallon sump under it. I'm guessing in total about 13000 to 15000lbs in this area
 
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I'm not a structural engineer so take this for what it is (opinion).
Hard to say exactly without knowing the specs of your particular floor, but, I think the average slab pour is done to ~ 3,000-3,500 psi. Now for the other part.
What is under the concrete? If its granite then you can put just about anything on it.
If part of the year its full of water and then drys out swelling can occur. Maybe a mix of sand, rock, clay, ect... example:

_________________________________

XXXXXX..................XXXXXXXXXXXXXXX

Where "X" is rock and "." is sand. If you put a heavy object over the sand the concrete will crack depending on how heavy the object is and how far away it is from the nearest X. Engineers call it a "cantilever".

Its a guess. If it was me I would dig out what there and drill some support footings. Maybe you could even sink the floor a bit and put in a drain under the tank to catch water that might find its way out of the tank.

Yeah I did that last time. I just hate the mess it makes and the time to do it. I'd like to move in soon. I am a bit confused by what I keep reading on the internet about the psi thing. I was calculating average per square feet, but reality is the stand only touches the ground in a few places, not evenly overall.
 
Yeah I did that last time. I just hate the mess it makes and the time to do it. I'd like to move in soon. I am a bit confused by what I keep reading on the internet about the psi thing. I was calculating average per square feet, but reality is the stand only touches the ground in a few places, not evenly overall.

In a machine shop sometimes heavy equipment is placed on steel plates to disperse the load. Since your stand only touches in a few places maybe go to the scrap metal place and get some 1/4 steel plates for under the stand or 1 big one, and let it go at that.
 
My 860g is sitting on my concrete slab at my townhome. It’s in CA so not sure what the codes are for structures here but it has been fine. My old 800g was in the garage also on an unmodified slab with no issurpes either
 
My 860g is sitting on my concrete slab at my townhome. It's in CA so not sure what the codes are for structures here but it has been fine. My old 800g was in the garage also on an unmodified slab with no issurpes either

Ok cool thanks. The lfs and the manufacturer think it will work so I guess I'll give it a shot
 
My 860g is sitting on my concrete slab at my townhome. It's in CA so not sure what the codes are for structures here but it has been fine. My old 800g was in the garage also on an unmodified slab with no issurpes either

I'm up North in Ca. House is 3 years old, dirt, then thin layer of gravel, rebar, cement. I am not an engineer but I seem to recall our home having 8" slab. I believe it is anyway. If in doubt you could always call the local city building / permit or planning office. I've had a couple questions and they typically answer. If they are not sure they could recommend an engineer. Again, our slab is 8" if I remember correctly and I have a 240 gallon sitting on it.

One other thing I guess would be to check the actual flooring if you are placing it directly on it. If you are direct on the slab probably not a big deal. Tile, engineered laminate, wood, etc may have weight bearing limits. That would be the only concern but when in doubt check :D
 
You're downsizing by nearly 500 gallons... over twice the minimum limit for being in Large Tanks forum. :0)

I gotta check out your current system... it's been a while. Care to share any pics??
 
Keep in mind, a big duel lie truck could park on a 4” slab and have no cracking or issues do to the weight. That’s about 4K lbs. yes the weight may be dispersed slightly differently but not much. A 500g tank is about that same weight.
 
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