To Styro or Not to Styro?

[hcky4206sic6]

While I have the attention of all who are posting on here, I wanted to draw your attention to this thread to see if you could help me out... especially the problem towards the end of the thread.

http://www.monsterfishkeepers.com/forums/showthread.php?p=3006167&posted=1#post3006167

I don't mean to draw people away from this conversation, just looking for helpful info from the people who seem to know a lot about forces that act upon the tanks. And to the individuals who already posted on that thread, thanks (oh and the plot thickens)...

 

[Pharaoh]

You guys are hung up on incorrectly thinking foam is used to level the tank. It is NOT!

The foam is there only to protect the tank from twisting forces that causes seams to split and glass to crack.

Please explain you answer. What physical composition of foam will eliminate the twisiting force that ruin a tank? How does foam negate the twisting. Please support all answers with factual evidence.

 

[Pharaoh]

I also bumped this post because there are many people who do in fact think that foam will level a tank.

 

[Pharaoh]

Glad to see I could be the cause of resparking a hot topic, ha! I posted the pic you asked for on the thread I started... see what you can make from it, if you could.

It wasn't you. It was the fact that three people in a row gave you an incorrect answer. somewhere along the line, someone has to give some factual info.

 

[vfc]

12 Volt Man,
I already posted the results of foam compression rates of various types of foam (both stryfoam and closed cell mats) on page 11 of this thread. I also posted an excel spreadsheet of the force per inch frame of many of the common tanks.

Your 150G tank only exerts about 8 lbs/frame inch. 3/4" closed cell foam will compress about 20% when the tank is full. So the remaining 80% (like a car shock) absorbs the twisting force. Styrofoam is way too stiff. It takes about 25 lbs/frame inch to start making a dent in it.


Pharaoh,
I'm worried about the advice you are giving on this forum. To demonstrate twisting force, take 12 Volt's Man's empty 150G tank, put it on a perfectly flat-level stand and place a silver dollar on the front left corner. You will notice that the rear left corner is now off the stand about the same distance. Now fill the tank with the usual gravel, rocks, and water. You will notice the rear left corner is closer to the stand then it was when empty. That is a twisting force and the cause of most leaks, cracked glass, and cracked frames.

Now empty the tank, cut a 3/4" closed-cell mat into strips and place them on the outer perimeter of the stand and under any plastic bottom braces the tank may have (a 150G has one center brace). Since the foam is on the perimeter it will not push up on the glass bottom. Now place the silver dollar on the front left corner (on top of the foam). Now fill the tank with gravel/rock/water. You will notice the silver dollar harmlessly sinks into the foam and the rear left corner of the tank is making full contact. "Twisting force has been eliminated by foam".

 

[12 Volt Man]

(a 150G has one center brace

only if its a Perfecto. Aqueon 150's have two. they are better built

 

[12 Volt Man]

what I was sort of getting at with my post was where is the twisting force coming from on a properly set up tank/stand that has settled in on a floor? there shouldn't be any.

unless the floor is sagging in unevenly. but if that is happening, you have a setup a tank that is way too heavy for your floor..

 

[vfc]

Each floor joist sags a different amount over a varying degree of time. The same occurs in a wooden stand.

I can offer three examples of wooden stands changing over time from the tanks I have in the basement (concrete floor).

- One stand is store bought. It has solid wood side panels but less structurally sound in the center. It sagged in the middle after a year. After three years the center gap is even larger.

- I built one stand for a 75G using six 4x4 suds for the legs. The concrete floor slopes left to right and front to back. It took quite a while to make 6 different thickness shims to get the top perfectly flat and level. After 6 months two of the legs had shrunk more than the other four; I was able to side the shims out from under the legs with no effort.

- I built another stand before I purchased the tank. I built it to support either a 6' x 18" width tank or a 4' or 5' x 24" width tank. The stand was super solid and perfectly level/flat. After a year, two 1/8" gaps opened up between the legs and the notched horizontal support beams.

The point is, wood used for a stand and floors is always changing. You need something that continually adjust to the changes and eliminate stress on the tank.

 

[The1and only]

The point is, wood used for a stand and floors is always changing. You need something that continually adjust to the changes and eliminate stress on the tank.

That is why the advise I give is if it is on wood get used to breaking the tank down every few years and releveling it. That is also why my larger tanks go on steel stands on a concrete floor with adjustable legs. Wood is always changing but but styrofoam is not the be all end all answer.

 

[12 Volt Man]

the main reason I chose the steel stand for my 150 was that I didn't trust the Aqueon/Perfecto pine stands over the long term

now I am even more glad I chose steel.