Floor Support for 225 gallon tank

[Andrew Schubert]

I’m setting up a 225 gallon tank on my main floor (basement underneath). The basement is using open web floor joists. The tank will be against one outside wall and sitting directly on 2 of the floor joists. I will also be adding a “fish room” below the tank which I’m sure will give some extra support to the tank weight. I plan on also adding some support columns just to be safe, but wondering if I need to pour a footer for these columns or not. Nothing I’m finding online is giving me any answers. I’m thinking it would be fine to not have a footer since the columns would just be providing secondary support. Thoughts? Suggestions for others with large tanks. I figure the total weight of the tank will be around 2,300 pounds.

 

[MERKEY]

If the basement is concrete (depending on how thick) you wouldn't need to but it may be a good idea to limit stress on the floor and future cracking if it is too thin...

 

[Max93]

I would hire a structural engineer to double check.
i put my tank on the main floor (waterbox 220.6g with basement directly underneath.

I had the structural engineer that built my house confirm that the roof joists where enough to hold the weight of an entire football team jumping up and down. He actually saw the tank once it was filled with water and also said it’s fine because I put it against the foundation of the house, perpendicular to the roof joists. I have roof joists every 16” so there’s about 4 or 5 of them holding the tank.

I still wish I put it in the basement instead, but who knew how we would get it down there without destroying the stair rails.

I also learn that every square foot can hold something like 40 pounds, per code. Of course this is how They calculate the weight an entire floor can hold. I’m not an expert and I could be wrong on the 40 pounds thing, just going off of memory.

seeing your joists, I would definitely add support or maybe consider using the basement instead. How old is your house? That will also determine the importance of adding support (although, better more support than none).
My tank weighs about 2700-2900lbs with water sand stand glass lights rocks and all. I figure if it’s gonna break through the floor the tank will spring a leak first before the floor ever collapses.

 

[Johnz]

Those floor joists are usually rated at 50 psf live load. You can exceed that in a given spot, ie, a 200 lb man standing on one leg won't crash a floor. But 2300 lbs in a 12 sq ft area might be pushing it. You want a continuous load path from each corner of the tank to the floor. I would add blocking on the cement wall to the plywood above to support the back end, and columns with double 2 x 8 blocking, making contact with the plywood if that is where the corner is, on the front. That is modern construction, the concrete floor below should not have a problem with the weight.

I am a general contractor, not an engineer. The safe thing to do is find a local engineer and have them do the math and draw a sketch. Otherwise an experienced carpenter should be able to do the job.

 

[Andrew Schubert]

Those floor joists are usually rated at 50 psf live load. You can exceed that in a given spot, ie, a 200 lb man standing on one leg won't crash a floor. But 2300 lbs in a 12 sq ft area might be pushing it. You want a continuous load path from each corner of the tank to the floor. I would add blocking on the cement wall to the plywood above to support the back end, and columns with double 2 x 8 blocking, making contact with the plywood if that is where the corner is, on the front. That is modern construction, the concrete floor below should not have a problem with the weight.

I am a general contractor, not an engineer. The safe thing to do is find a local engineer and have them do the math and draw a sketch. Otherwise an experienced carpenter should be able to do the job.

Thanks for the suggestions. How does this look for a start. Added a couple boards against the trust and top back cement wall. Added 3/4 plywood boards on each side of the trusts and finished it off with an extra 2x4 on the bottom trust. Also included double 2x12 between trusts. Tomorrow I plan on adding a 4x4 column directly below each of the doubled up 2x12. 3 other 4x4 coulombs against the cement wall. And the left side will be the outside wall of my “fish room” to which I plan on throwing in a couple 4x4 for studs there as well.

 

[Johnz]

Very impressive. I've used osb nailed to a truss to stiffen it before, what you've done far exceeds that. I can't see the fasteners but 8d nails through the plywood all along the truss members @ 6 " o.c. is what I would do. A 4 x 4 post under each truss will be more than sufficient. You will be able to park a Mac truck on it.

 

[Andrew Schubert]

Very impressive. I've used osb nailed to a truss to stiffen it before, what you've done far exceeds that. I can't see the fasteners but 8d nails through the plywood all along the truss members @ 6 " o.c. is what I would do. A 4 x 4 post under each truss will be more than sufficient. You will be able to park a Mac truck on it.

I actually used 3/8 lag screws as my fasteners, as well as titebond 3 wood glue to fasten the truss to the plywood. I didn’t add any fastener or glue directly to the members, just directly to the top and board 2x4. Was afraid to add them to the members, as I didn’t know if that somehow could throw the balance of the members off somehow. Maybe I will go back and do that as well.

 

[exnisstech]

I had two 180 gallon tanks and a 150 gallon all at once. Both of the 180s in the living room and the 150 less than 8 ft away in the dining room. I ran them for years and everything was fine. I did add a couple pole jacks in the basement with a make shift beam spanning 3 floor joists. I just put the pole jacks on the concrete in the basement.

 

[muggle0981]

Everyones story is different

i have 180g on my main level

spans 5-6 joins and almost sits directly on steel beam that spans the tank

structural engineer can be crazy expensive but worth it

luckily knew a guy who essentially evaluates new construction and structures for building codes and what not

looked at my situation and basically said good to go, and since the 180 stand was touching all the floor it was spreading weight more evenly vs my 120g stand that was putting all the weight to 4 leg points

so much stress in this hobby

 

[jhuntstl]

The hangers were unnecessary imo, but they make it look good. If an inspector came by, they'd approve.

The 4x4s are doing nothing near the foundation, they can be removed. Your foundation is already offering more than enough support. Adding the 4x4s directly under the floor joist at the appropriate projection would be a good addition. You will eliminate any potential for bounce.

 

[Andrew Schubert]

Everyones story is different

i have 180g on my main level

spans 5-6 joins and almost sits directly on steel beam that spans the tank

structural engineer can be crazy expensive but worth it

luckily knew a guy who essentially evaluates new construction and structures for building codes and what not

looked at my situation and basically said good to go, and since the 180 stand was touching all the floor it was spreading weight more evenly vs my 120g stand that was putting all the weight to 4 leg points

so much stress in this hobby

I built the stand for the tank purposefully so that the entire structure touches the floor so that the weight will be more spread out, just as you said.

 

[Andrew Schubert]

The hangers were unnecessary imo, but they make it look good. If an inspector came by, they'd approve.

The 4x4s are doing nothing near the foundation, they can be removed. Your foundation is already offering more than enough support. Adding the 4x4s directly under the floor joist at the appropriate projection would be a good addition. You will eliminate any potential for bounce.

I was thinking the same thing about the hangers as I was putting them up. ESP since the columns are going under them. I’m planning on putting the columns on the 2x12, not the joist directly. This is because I have open webbing truss system. I feel if I put the support columns on the truss it actually would negatively effect the floor, since the bottom truss is designed to bow up under stress, a column on one would only provide more stress on the truss I would believe.

 

[Andrew Schubert]

I had two 180 gallon tanks and a 150 gallon all at once. Both of the 180s in the living room and the 150 less than 8 ft away in the dining room. I ran them for years and everything was fine. I did add a couple pole jacks in the basement with a make shift beam spanning 3 floor joists. I just put the pole jacks on the concrete in the basement.

Have u seen any issues with that much weight in one spot on the cement. I was thinking about putting a 4x8 sheet of plywood under my entire support system to more evenly distribute the weight across the concrete.

 

[exnisstech]

Around here concrete floors are typically 4 inches thick as a minimum so I don't think it would be needed. But I'm not an engineer. I have worked construction and have had to jack hammer concrete for removal and it is very strong and it's usually reinforced with rebar or strong steel mesh. I don't think I would do the plywood if your talking about on the floor. I don't think it would really add any strength and would a place for moisture to accumulate.

 

[Andrew Schubert]

Around here concrete floors are typically 4 inches thick as a minimum so I don't think it would be needed. But I'm not an engineer. I have worked construction and have had to jack hammer concrete for removal and it is very strong and it's usually reinforced with rebar or strong steel mesh. I don't think I would do the plywood if your talking about on the floor. I don't think it would really add any strength and would a place for moisture to accumulate.

Never thought about the moisture thing. That is a good point.

 

[jhuntstl]

I was thinking the same thing about the hangers as I was putting them up. ESP since the columns are going under them. I’m planning on putting the columns on the 2x12, not the joist directly. This is because I have open webbing truss system. I feel if I put the support columns on the truss it actually would negatively effect the floor, since the bottom truss is designed to bow up under stress, a column on one would only provide more stress on the truss I would believe.

I get what you're saying with the open web design. With the way you've braced them, I think it would be fine to support them directly underneath.

I am a carpenter with no experience with open webbed joists, so take my semi inebriated advice with a grain of salt.