Shims leveling tank?

ReefCowboy

New member
So I have a 150gal that Im finally getting ready to set up.
It will be on the basement, where I already laid some plank vinyl and the room is ready to go.

Problem is the spot where the tank will be going is unleveled. I see recommendations of shims to help that, but wanted to check if anyone has better ideas.

The floor underneath is concrete. If shims are the way to go, does anyone recommend a certain type/brand? Shims lenght? Are shims safe first of all for a tank? Footprint of the stand is 61”x 24”. It is well built, by a local tank/stand manufacturer(not composite wood).
The tank spot leans to the rear and right side of the room.

Thanks for all help
 
Most everyone uses shims to level tank, not many floors are perfectly level.
Cedar or composite, both work fine.
 
If u go with composite I would also get a pack of cedar. Most composite shims the small end are still a little thick, around 3/32” so a little less then 1/8”. Cedar shims are made to where they basically go down to nothing on the small end. So u can shim a little 1/16” gap if need be. So use the composite if u want but have a couple cedar just Incase need to shim a small gap.

When u level the stand the first thing to do is figure out whatever corner is the highest to get a starting point. Once u do that go around & get all four corners level. Once it’s level u can come back & place the shims inbetween if they are needed.
 
If u go with composite I would also get a pack of cedar. Most composite shims the small end are still a little thick, around 3/32" so a little less then 1/8". Cedar shims are made to where they basically go down to nothing on the small end. So u can shim a little 1/16" gap if need be. So use the composite if u want but have a couple cedar just Incase need to shim a small gap.

When u level the stand the first thing to do is figure out whatever corner is the highest to get a starting point. Once u do that go around & get all four corners level. Once it's level u can come back & place the shims inbetween if they are needed.

Thank you. Now how many shims are needed? I figure a tank is heavy and although the shims can withstand the weight, do i place many on each side for extra support?
 
I used composite shims. Take your time. Using tap water. I filled my tank 1/3 rechecked. Drain re-level. I did this a couple times till I had it full and level. Was a bit of a pain, but I didnt want to get rocks and saltwater in and have an issue. I have a Python thats makes filling and draining from the tap super easy.
 
Thank you. Now how many shims are needed? I figure a tank is heavy and although the shims can withstand the weight, do i place many on each side for extra support?

Tanks are heavy but the load is quite spread out. My tank weights 4000 pounds but that is spread over 12 2x4s with a total cross section of ~60 square inches, so the pressure under those is a little over 60 PSI. A cheap plastic shim can easily handle 100x that.

The amount of shims you need is very much depends on the construction of the stand, but you need to have 100% shim support under the vertical supports. If you are going to have a sump underneath you should also make sure to shim underneath where-ever the load of that sump is going to be distributed. But otherwise you don't really need any shims anywhere load isn't being distributed, however I'm sure most people put them there anyways. Better safe than sorry.
 
Alternative to shims on concrete floors is to use concrete floor leveler..
That is assuming its the floor and not the stand
 
You need two shims under each post (except the high corner), or more if the floor is really off. You don't want a wedge under each post, you want something flat, and two shims shoved opposite and on top of each other will give you a flat.
 
Noticed the floor has really unleveled spots. Single shims wont bring the tank to the proper level on the bad side. Can shims be stacked and remain safe? What if I got a thin wood pannel sort of covering one side of the stand footprint, where the floor is at its worst and then slid shims under that thin wood pannel? I guess it would act like a shim, right?

Im thinking to get this to where its needed, I would have to stack maybe three shims...:(
 
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That is fine, stack shims.
I'm a carpenter myself, and I'm kinda fussy, so I have my preferences, so I really like the long shims best, the ones that are red cedar, not clear, and really it's mainly the way they snap clean when scored.
The short clear ones usually splinter.
I also like that they are not such a wedge compared to shorts, they tend to snug up and stay better IMO

Composite has it's pluses, if on carpet you can snap them upwards w/out scoring w/ a razor knife, risking cutting carpet.

Both are equally strong and both hold up even around water.

I did once do the concrete leveler as Mcgyver mentioned, that was an uneven slate stone floor, shims were not really an option that time.
It worked fine, but takes a little more work than usually needed.

I laid heavy plastic down on that so I could remove clean in case I moved tank, which I did, worked like a charm.

I suggest about every 6" place shims after you've leveled tank, and also agree a check mid fill of tank is a good idea.
 
That is fine, stack shims.
I'm a carpenter myself, and I'm kinda fussy, so I have my preferences, so I really like the long shims best, the ones that are red cedar, not clear, and really it's mainly the way they snap clean when scored.
The short clear ones usually splinter.
I also like that they are not such a wedge compared to shorts, they tend to snug up and stay better IMO

Composite has it's pluses, if on carpet you can snap them upwards w/out scoring w/ a razor knife, risking cutting carpet.

Both are equally strong and both hold up even around water.

I did once do the concrete leveler as Mcgyver mentioned, that was an uneven slate stone floor, shims were not really an option that time.
It worked fine, but takes a little more work than usually needed.

I laid heavy plastic down on that so I could remove clean in case I moved tank, which I did, worked like a charm.

I suggest about every 6" place shims after you've leveled tank, and also agree a check mid fill of tank is a good idea.


Thank you so much for the advice...I'm a complete newbie to the shim world. So I have at Home Depot the choice of cedar/wood or composite. There is also a brand labeled "contractor"s choice which is wood but longer.

My floor is vinyl planks. What type should I get? Pros and cons of composite vs wood?
 
I prefer the long ones in cedar, a lot of people think you need composite around water or that it's better, they all work fine, I just always lean towards natural products over plastics when given choice.
 
I would not shim the tank. You put stress on the tank. I would shim the stand to get it level. Make sure the surface the tank lay on is flat, meaning on the same plane, then your tank will not crack, even if one side is higher than the other side.
 
I would not shim the tank. You put stress on the tank. I would shim the stand to get it level. Make sure the surface the tank lay on is flat, meaning on the same plane, then your tank will not crack, even if one side is higher than the other side.

Yes you are correct, I would never shim the tank. Will shim the stand to level, the tank will sit on a flat surface, over a 1/4" foam mat.
 
So I put the tank and stand finally together. The floor is so unlevel that I must put up a picture so everyone can laugh.

 
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Yes I figured discussing concrete floor in very first post made it clear we are shimming at floor under stand, but yes to point out the obvious, we never shim between tank and stand...:rolleyes:

Hard to tell exactly how bad that is just in pic, (especially shot at an angle)but for example my last place was a 1/2" out of level in 4', that was bad!

Your stand looks nice, after shimming at floor maybe trim out w/ some quater round or shoe moulding to hide the shim area.
 
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