# Tanks on uneven floors?



## HaeSuse (Aug 18, 2016)

This came from another thread, but I was worried it would get buried, and not answered, being very tangential to the original thread to begin with.



Olskule said:


> The one tank-killer I am sure of is an uneven platform, especially with larger aquariums (3'-4' long +), and that includes the floor/foundation the stand is sitting on. If there is any unevenness, the tank and stand will settle over time, causing stress on the glass and/or joints which will result in a wet floor and possibly some very sudden heart-racing moments in the future.


Hmmmmm.... How true is this? I'm a veteran fish keeper (almost 20 years now), and I've never been overly worried about the floor being level. I have moved a tank around a bit, to find the MOST level spot in the area I want it, but never have I shimmed it up, or tried to add wood to the tank stand to adjust for the floor's unevenness. Also, I've never had issues from a small slope on the floor. 

I'm just now setting up my new 55G tank, and after I got it all up and filled, I noticed that the water on one end was a good 1/8" lower than on the other end. I can measure the actual difference when I get home. Could be as little as 1/16". 

Should I shim it? Drain it, and make some modifications to the floor, before refilling and replacing? I don't have many options on placement for the thing. I have too many darned children and animals running around. 

Thoughts?


Thanks in Advance.


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## Hersheyb (Aug 31, 2015)

Fix the floor or move the tank to an even floor. Tank will wear out over time...


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## Olskule (Jan 28, 2010)

Uneven and unlevel are two different things when it comes to tanks and stands. "Unlevel" refers to the water being slightly deeper on one end than the other (or front to back), and is purely a matter of preference and how obsessive you happen to be. If it's not much (either the unlevelness of the water or your obsessiveness), just keeping the tank full enough that the offensive water level is hidden by the top frame will work just fine. However, "uneven" in regard to the tank and stand refers to the points of support for the aquarium being on different planes, as in one corner being higher than the other three, and causes too much stress to be focused on one point of the tank (not distributed evenly as it should be), and could result in either a seam letting go (or just leaking) or a pane cracking. This usually happens gradually until the limit of endurance is reached, then things happen quite suddenly. 

With an unlevel tank, the bottom corners or feet of the stand can be shimmed with most anything that will not compress over time (I use pennies), but using too many shims, or shimming more than two corners could result in the setup being unsteady. If a large amount of shimming is required, use thicker shims instead of too many thinner shims.

With an uneven stand or floor, the problem should be corrected before the aquarium is placed and filled. If it a situation where the stand itself is "square" (the aquarium sits flush on all corners), but rocks on diagonally opposite corners (three feet or corners on the floor and one foot or corner not touching the floor), then the floor is uneven and the stand itself can be shimmed to keep it from rocking before filling the tank with water. (Which corner to shim can be determined by using a level on the stand, or else just enough water in the aquarium to match the water level to the bottom frame of the tank.)

If it is the stand itself that is uneven, such as a metal stand that somehow got twisted or a wooden stand that is warped, or maybe the stand just wasn't made correctly in the first place, then the empty aquarium will rock diagonally on the stand itself. This problem requires equalizing the support and weight of the tank evenly across its footprint, and can be easily solved by cutting a piece of styrofoam (at least 1/2" thick) to fit the footprint of the aquarium and placing it between the tank and the stand. (A length of vinyl electrical tape can be wrapped around the edges of the styrofoam to hide it, and blends especially well with basic black aquarium frames.) The styrofoam is rigid enough over the length of the aquarium to support the weight, yet soft enough at any one point to absorb any imperfections in the stand's surface, including one slightly higher corner. Keep in mind that the stand itself may need to be shimmed at the floor as well, and don't be tempted to depend on the weight of the filled aquarium to do the work of straightening out the stand, because before the stand adjusts itself (as with a wooden stand), it may put uneven pressure on the tank, which is what you want to avoid. That MIGHT work alright with a wooden stand, and a metal stand that is fabricated from formed sheet metal may likely be flexible enough to give in, but not necessarily a welded, solid wrought-iron stand, and why take the chance when the solution is so simple and cheap?

Also to be considered is that almost all house/building foundations are subject to settling, unless it is built on solid rock; most places aren't. If the foundation settles unevenly in the wrong place, even dropping one corner of the aquarium stand just 1/8th of an inch, then that's a LOT of torquing pressure on the tank, and most tanks are not built to withstand that type of stress, so I always assume the worst and put a sheet of styrofoam underneath my aquariums. This principle of uneven stress applies differently for different sizes of tanks, with smaller volumes generally being less susceptible, due to less water weight and pressure; I can't imagine a problem with any aquarium small enough to be carried by two people when it is full, but when you start adding up the weight of water, substrate and the tank itself, it equals a LOT of stress on the glass and seams.

Of course, all of this is reiterating what you have already quoted me as saying in a previous post, but I wanted to add to what I wrote before in order to both be more thorough in my explanation and to clarify the difference between what I call "unlevel" and "uneven". Hope this helps. 

Olskule


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## PlantedRich (Jul 21, 2010)

I would not bother for that small incline. I deem it one of the overblown items in the hobby. When I have had the problem was when the slope was enough that the water level peaked out from behind the trim at one end. Part of the problem is dependant on how the stand is built. If it is a wimpy stand that can't stand the strain, it is more likely to be a problem. I currently have a 75 gallon on a DIY stand that has been that way for months because I'm going to be moving it and the rollers are the handy way to move tanks and stands. But then I built the stand and know it is solid. If a slope of 1/8 inch in four feet is so much that the sideways motion gets to the stand, I would not want to lean on it to do any work! 
Obviously, when the tank is tilted, there is more pressure put on the end glass but then how much more than is already there is the big question. So if two pounds more pressure is enough to blow the end seal, was it really a good seal to start? I don't allow twists but worry very little about getting them totally level.


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