100 gallon tank on crawl space?

headdr

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I'm considering putting a 100 gallon tank in my kitchen on a crawl space. Anyone got experience doing this? Is it a mistake? I can put it perpendicular to the exterior wall right against it on the short end. Going to be parallel with joists but it is 48 x 24 x 20, so the 24 will cover 2 joists. I feel like the 3/4 inch floor decking will distribute it across 3 joists. Am I nuts?
 

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I'm considering putting a 100 gallon tank in my kitchen on a crawl space. Anyone got experience doing this? Is it a mistake? I can put it perpendicular to the exterior wall right against it on the short end. Going to be parallel with joists but it is 48 x 24 x 20, so the 24 will cover 2 joists. I feel like the 3/4 inch floor decking will distribute it across 3 joists. Am I nuts?
I'm asking a similar question how ever I'm moving potentially my tank out of the kitchen. Yet, it depends on your centers and spans. 16inch vs 24 inch. Also your joist width, ie 8" or 10", single or doubled. You're putting a half ton system. So start with that.
 
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The joists are architectural beams(composite wooden I- beams). 18 inches on center with a 16 inch web height. They span the width of my basement. 24'. Tank would span at least 2 beams.
 

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headdr

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So all I am hearing on most of these videos is 40 lb/ sqft. Using water weight of approx 8.6lb. that's 4.6 gallon. Divide by .13 ft3/gallon water. That's .6 ft cubed. Divide that by 1 square foot and that's 7.25" of water depth. So the deepest tank you can have per code is 7.25 deep. Gotta be another way to estimate what a floor can handle.
 

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So all I am hearing on most of these videos is 40 lb/ sqft. Using water weight of approx 8.6lb. that's 4.6 gallon. Divide by .13 ft3/gallon water. That's .6 ft cubed. Divide that by 1 square foot and that's 7.25" of water depth. So the deepest tank you can have per code is 7.25 deep. Gotta be another way to estimate what a floor can handle.
Those are based off a load over the entire floor. Ie a non bedroom floorspace by code has to support 40/square foot over the entire floor as i understand it. This does not mean a 300lb person is at risk of falling through the floor if he stands in one place. A dozen 300lb people lined up across the floor is a risk....

As for an answer i am no engineer and what nt advise yes or no. I will say personally i never worry about anything 120g or under especially if on a exterior wall.
 

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I would not be concerned. Those floor joists are holding the weight of your house. A fish tank is not that heavy. My first tank was 75 gallons and was in a mobile home. That was over 30 years ago but it was not an issue. Think of furniture like waterbeds. They don't fall through floors. A hundred gallon tank your looking at 800 lbs.
 
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I did the math. About 1500lbs static load including tank stand rock and sump. I have no way of bracing it from underneath, it is a finished ceiling basement. A pole would look funny.
 

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I did the math. About 1500lbs static load including tank stand rock and sump. I have no way of bracing it from underneath, it is a finished ceiling basement. A pole would look funny.

In first post you said crawlspace. I am confused did you dig it out, put in a basement, and finish it in the past week?
 

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I still would not be concerned unless you have had termites.
Also I think you may be overestimating the weight.
100 gallon tank does not really hold 100 gallons so max water is 800 lbs if there were No rock displacing water.
I would not think you would put more than 100lbs of rock but of course you could.
Not sure what you thinking for a sump but I would guess 20-30 gallons of actual water which would be approx. 200 lbs and then a stand. So I would guess maybe 1000-1100 lbs total. I think any decent built house floor can handle that weight.
 

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I still would not be concerned unless you have had termites.
Also I think you may be overestimating the weight.
100 gallon tank does not really hold 100 gallons so max water is 800 lbs if there were No rock displacing water.
I would not think you would put more than 100lbs of rock but of course you could.
Not sure what you thinking for a sump but I would guess 20-30 gallons of actual water which would be approx. 200 lbs and then a stand. So I would guess maybe 1000-1100 lbs total. I think any decent built house floor can handle that weight.

Couple big things you left out:
The tank ~200 lbs unless thick glass then maybe double
Sand ~100-250 lbs assuming not going bb

Add in miscellaneous items and equipment (pumps, sump itself, ato container?, Etc). 100lbs rock in a 100g is not at all unreasonable. Some would run with double that especially if using genuine rock.

1500 estimate seems reasonable to me
 
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