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Aquarist Forums => Freshwater General Discussions => Topic started by: bamboofish on November 29, 2007, 05:34:39 PM

Title: new setup question???
Post by: bamboofish on November 29, 2007, 05:34:39 PM
Hi Guys,

I just set up a 75 gal. I leveled the stand, did the styrofoam thing under the tank. Now that it's full, it is off level by approx. 1/4 inch leaning to the front.
Is this a big problem or can i just live with it that way????

Rich
Title: Re: new setup question???
Post by: babblefish1960 on November 29, 2007, 06:41:28 PM
You need to revisit the levelling of your stand, I am unsure how large the tank in question is, but it does matter, in the long run, the additional pressure on the front with reduced pressure on the back will cause unequal stress across the joints in a mathematical displacement similar to a trapezoid.  The glass, flexible as it is, will not suffer this disparity for all time, again dependent upon the size of tank involved.  Shims under the stand in a manner relative to tank stand construction will rectify the situation. Remove some water to make the thing lighter, and do not push them under with a hammer.  Use a lever to raise the stand ever so gently and only small bits at a time, then slip the shim underneath on both sides checking repeatedly that you are lifting it evenly and squarely.  If this is not done carefully, you can damage the tank.  Keep adjusting making sure the entire tank is moved evenly and you should be able to bring it up to square and level.

Good luck, keep the movement slow and in small increments and you should be fine.

This should be done with a few people to ensure even moving and condition of all circumstances surrounding the move.  DO NOT ADJUST THE TANK, ONLY THE STAND!

There, I yelled, now you know it is a serious method, if it makes you nervous, remove most of the water and you should find it much easier. :)
Title: Re: new setup question???
Post by: renadia on November 29, 2007, 07:13:32 PM
OH GOD you have made me nervous now   :(

I have the same problem with my 75 gal  :-\

:o    ???    :-[    :-\   :'( 

Helppppppppppppppppppppp
Title: Re: new setup question???
Post by: babblefish1960 on November 29, 2007, 07:35:51 PM
Silly me, you said it was a 75 gallon, well, this creates another set of forces when collected with the first set, this is similar to the trapezoid type of problem, and something called torsion, this has the net effect of wringing the tank like a towel, but clearly, glass is less forgiving of this sort of action, and it is harder to notice until you reach the upper shear stress limits.

It really isn't a huge problem to fix.  As I mentioned, adjust the stand, not the tank and remove as much water as you can to lessen the stressors.

With a length of four feet however, you must raise this in ever so small steps evenly across the entire length of the tank.  You will be glad you did, as you will likely never have to think about it again.

The problem with torsion and trapezoidal stress is that the panels of glass, though somewhat flexible, are pinioned by their positions and act as levers on the mechanical silicone joints, and easily predicted as to where the leaks shall begin, provided you do not have a blow out first.

I am painting the absolute worst cases as a scenario that can catch each anad every tank that is out there.  Obviously, not everyone experiences this in the same degree, and some will swear they have never heard of these problems.  It is something like driving through redlights, most people get away with it every day, but the odds are against you doing that continually without one day getting t-boned by someone who drives through fresh green lights at speed.

It isn't a game I would play, and I have seen many accidents, on the road and in the living room with tanks that could have been adjusted.  You paid good money for your equipment, and even more usually for the contents, it seems counter-productive to skip a very important step just because you have gotten away with it up until now. :)
Title: Re: new setup question???
Post by: bamboofish on November 29, 2007, 07:46:30 PM
OK thanks,
how about this.
This old house we own has slightly slanted floors, I can fix that as you say. But they are also wobbly a bit when you walk by, and they shake the tank or Tv stand, or anything else in this room. could that pose a problem??? 75 gal. 48X18x24.
As the water drains out the stand is creaking. ALLLLL that water.........

Rich
Title: Re: new setup question???
Post by: babblefish1960 on November 29, 2007, 08:12:47 PM
Years and years ago in my first old home, I had some very large tanks (over 300 gallons each) in the living room, back when refrigerators and stoves came in avocado and mustard, same problem, the tanks wobbled as you walked past.  It was frightening at first, but you tended to get accustomed to it.  What I did to make them more secure was to first put the metal stands on thick plywood on the floor, this helps spread the load out along several joists, and from underneath, I placed two lally columns with a small beam between them and the joists to help tie the movement of the joists together and shorten their span between beams.  This helped make them much more solid.  In all the years that those tanks were like that, they never leaked despite the wobble, and I attribute this to equal movement as well as being statically planar square in all three axes.  Which is to say that they were vertical, flat and level.  Even were you to place 1" x 2" slats under the breadth of the tank and shim then, you would find more stability, it sounds as though the adding of water to the tank is compressing the joists into a moment where the depression is noticeable.  You must compensate until it is correct under load.  Good luck, and take heart, once you are done, this will be much more relaxing. ;)
Title: Re: new setup question???
Post by: bamboofish on November 29, 2007, 08:45:05 PM
Thanks,
I've shimmed it, now it's perfectly level. Now to add back the water........I'm not going to worry about the wobbling floor.

Rich
Title: Re: new setup question???
Post by: Toss on November 30, 2007, 06:08:58 PM
Before you fill it again with water, plan your aquascaping in term of gravel, rocks and driftwood if you use any. You may have to dump that 75 gal of water again when you do aquascaping :P
Title: Re: new setup question???
Post by: busdriver on November 30, 2007, 09:31:34 PM
Listen to Babble, I can tell you from experience, if your tank is NOT level you will regret it.
I had a 150 gal. that I thought was level.

One o'clock in the morning, sitting beside the tank, on my computer, a god awful crack and a waterfall, what an awesome sight.

Take a look at the picture im my gallery, IN TANKS.
Title: Re: new setup question???
Post by: Brine on December 01, 2007, 11:58:45 AM
When I had a fishroom in Cambridge I actually lag bolted the stands to the wall studs. I had a wall full of tanks so I wanted to be sure everything stayed where it was put. That way the only possible way they could wobble or become out of level was if the whole wall moved. NOT recommended for renters.  :o ;D
Title: Re: new setup question???
Post by: Nerine on December 01, 2007, 02:13:54 PM
Agreed, perfectly level is the way to go!! Cora and I drug the 75 all over the basement at my current place because the floor is SOOO unlevel!!! after a few hours we finally found the perfect spot for it on the floor...it's not where I wanted it, but it's where it is level and with least amount of shims!

upstairs the floor is wobbly but the tank is fine, it's level!