300 Gallon leveling on uneven floor.

[Hari Haran]

Need some advise leveling a 300 gallon tank, all went well until I found the concrete floor has a bump in the middle where I want to place the tank, with the bump in the middle the tank rocks side to side, there is a 3/4 inch gap on one side.

I used a 1/2 inch wood on the edge as the gap is not 3/4 from front to back, used shims every 8 inches all the way around the tank.

My question is would this work or I need to look at fixing the floor. Has anyone done something similar for a larger tank.

Thanks.

 

[TheWolfman]

I just went through a similar issue setting up my tank. Shims should be placed under the legs that are taking the load. No need to shim the entire bottom of the stand. Start with the four corners and then shim the middle as needed. Be sure to use a 6’ level or 8’ if you have it. A laser would be best.

 

[TheWolfman]

I just noticed the strip of ply that runs the length of the tank. I would ditch that as it will only make leveling the stand harder. You should only be using shims to level. Also you probably already know this but the stand should only be leveled before the tank is on it.

 

[Hari Haran]

I just noticed the strip of ply that runs the length of the tank. I would ditch that as it will only make leveling the stand harder. You should only be using shims to level. Also you probably already know this but the stand should only be leveled before the tank is on it.

Actually i had it leveled with tank and bit of water assuming the extra weight would give me accurate leveling needed.

i didnt have a 1/2 wood, ply was laying around so used it for the initial height as it needed like 4 shims which i felt could be unstable so i used a strip of wood for initial height and used just one of the shims for final leveling.

Any chance you could share some pictures of your tank after leveling.

 

[Nilsafeller]

Actually i had it leveled with tank and bit of water assuming the extra weight would give me accurate leveling needed.

i didnt have a 1/2 wood, ply was laying around so used it for the initial height as it needed like 4 shims which i felt could be unstable so i used a strip of wood for initial height and used just one of the shims for final leveling.

Any chance you could share some pictures of your tank after leveling.

I dont think on concrete it would matter if you level before or after tank sits on stand... but on my main floor I have hardwood... I leveled before tank and water and after filling, the tank actually sank a bit on one side... only a 1/16 inch over 6 feet but it still sank cause your sub floor and flooring will have some give...

 

[TheWolfman]

The reason you don’t level with water is your stand will experience some flex, and you won’t get an accurate level. Not to mention with water in it you probably won’t be able to shim to the height needed. By shimming the stand before the tanks in place you can be certain your stands perfectly level and true. There shouldn’t be any side to side or front to back rocking what so ever. I will take some pictures of my stand when I’m home and post them up for you.

 

[A201]

Most floors are imperfect, some more than others. Even after careful shimming, leveling perfection is unlikely.
As long as all four corners of the tank firmly rest on the stand, the stand doesn't sway and there is no obvious structural twisting, you're good.
It's not unusual for one end of a tank to be slightly higher than the other, depending on the slope of the floor.
Your situation looks extreme. You might consider using a masonry (concrete)
leveling product.

 

[Hari Haran]

Most floors are imperfect, some more than others. Even after careful shimming, leveling perfection is unlikely.
As long as all four corners of the tank firmly rest on the stand, the stand doesn't sway and there is no obvious structural twisting, you're good.
It's not unusual for one end of a tank to be slightly higher than the other, depending on the slope of the floor.
Your situation looks extreme. You might consider using a masonry (concrete)
leveling product.

Appreciate the reply.

Problem was the bump in concrete somewhere in the middle of the tank which is causing sides to out of level.

i have asked my contractor to see if he can shave out the bump, hoping that should fix the issue.

 

[Matteus]

The reason you don’t level with water is your stand will experience some flex, and you won’t get an accurate level. Not to mention with water in it you probably won’t be able to shim to the height needed. By shimming the stand before the tanks in place you can be certain your stands perfectly level and true. There shouldn’t be any side to side or front to back rocking what so ever. I will take some pictures of my stand when I’m home and post them up for you.

I think it should be done before water, add 1/3 water to double check What the stand will do with that flex. This is where you make final adjustments if needed. Then once the tank is full to make sure everything is still in order after it is filled. I don’t think you get a fully accurate level before there is water in it.
Also if there is any sort of trim on the top of the tank you may need to check if it is entirely even or that may affect your reading.

I have only set up a handful of tanks over 200g so I am no expert, but this is what I have always done and also watched much more experience people in the hobby do as well.

islandguy11 Barrett has experience with uneven 375g that caused leaks. Maybe he can chime in with some of his solutions.

 

[Hari Haran]

In regards to the amount of water, its an inch from bottom, i would say 20 gallon on a 300 gallon tank, i had it in there so i can see it change as i am levelling in addition to level scale.