Seals Blowing Out: Epidemic?

[grouper therapy]

Crewdawg1981;596167 wrote: ... And my new glass tank was sitting level on a stand with water in it for 6 weeks and had a failure. That hopefully doesnt get any worse before a replacement.

Sitting level does not guarantee that it will not fail, just one of the common causes. The term level is being used and really does not have anything to do with failure unless it is a way out of level and exerts too much pressure to one side, I don't think this is the case. Too often people set up their aquarium and throw a 12"-24" level across the front of a 72" stand and maybe one end ,check for level and fill it up. The tank should be sitting flat on the stand around the perimeter of the stand but if it is not it absolutely has to be in contact on all four corners(framed tank). If this doesn't happen then a twist as Jenn said is put on the tank.I've seen 2x stands (framing lumber) built with warped or no straight edge available and the tank sitting right on top. The foam idea under a framed stand is useless it only blocks the light you can see in the space and does nothing to evenly transfer the load as the foam does not compress evenly. If the foam magically flattened and leveled structures I assure you me and anyone else who has framed a house would use it everywhere we needed level and flat surfaces.

 

[crewdawg1981]

Oh I didnt mean to imply that being level meant it shouldnt have failed... was just pointing out that I put a level all over this thing and it appeared level (since this is one of the typical issues), and I had a crack occur. No idea why or how.

 

[ichthyoid]

JennM;596156 wrote: Foam is a good idea under acrylic tanks. IMO it doesn't belong under glass tanks. The frame of a glass tank, if it's not level, can compress the foam unevenly, and "help" it to twist. I have never seen any glass tank manufacturer recommend foam under a glass, framed tank.

Acrylic tanks need even support across the full surface of the bottom, foam can be useful for this. Glass tanks with frames only need support around the frame itself, and being level and evenly supported is very important.

Jenn

This is one time we may</em> not agree. If a tanks not level to begin with, a layer of foam may not be able to correct the offset. However, 'compliant' (ie-to have 'give') foundations help distribute uneven forces. It is a fundamental engineering technique. I have used foam by itself on smaller glass tanks, and 'sandwiched' between layers of plywood on larger ones. I also extend the foam beyond the edge of the tank frame, as this eliminates 'rolling'.

On the other hand, my O'Dell 55 sat for 30 years with nothing but 1/2 inch plywood under it. It should also be noted that plywood itself has some degree of compliance, as well. I am not a fan of 'chip board' for supporting a tank, either.

They just don't make things like they used to!

One of the reasons that silicone rubber adhesives work so well is that they are highly compliant materials, whereas glass is not.

FWIW- 'glass' is not a solid at all, but a highly viscous liquid. I know, that's hard to imagine but true. This was discovered when panes of stained glass windows from middle age's era cathedrals were found to be thicker at the bottom, than the top. This showed that they had 'flowed' downward from the effect of gravity over hundreds of years. This has since been shown to be fact via modern rheological testing, x-ray anlysis, etc. Metal impurities may be added to glass to form 'Crystal', which IS a solid.

The problem with glass is when you have a significant change in force over a small area. You may call it concentrated force if that helps envision it, but in the end that condition creates 'shear'. Shear forces are the enemy of high modulus materials, which include both glass and plastic (acrylic) tanks.

Panels of acrylic or glass detaching/leaking are an <u>adhesion failure</u>-IMO. This result may have been agrivated by shear forces, but in the end the 'joint' failed, NOT the core/'bulk' of the material itself. Material 'bulk' failures are usually more 'catastophic' in their manner of failure (cracks, breakage and shattering). Of course if the entire perimeter of the joint fails and the panel hits the floor and shatters, it would be difficult to assess the mode of failure without a microscopic evaluation of the joint portions. In the end, a good material analysis will reveal 'the smoking gun'. -JMHO

 

[tgriffin]

grouper therapy;596176 wrote: Sitting level does not guarantee that it will not fail, just one of the common causes. The term level is being used and really does not have anything to do with failure unless it is a way out of level and exerts too much pressure to one side, I don't think this is the case. Too often people set up their aquarium and throw a 12"-24" level across the front of a 72" stand and maybe one end ,check for level and fill it up. The tank should be sitting flat on the stand around the perimeter of the stand but if it is not it absolutely has to be in contact on all four corners(framed tank). If this doesn't happen then a twist as Jenn said is put on the tank.I've seen 2x stands (framing lumber) built with warped or no straight edge available and the tank sitting right on top. The foam idea under a framed stand is useless it only blocks the light you can see in the space and does nothing to evenly transfer the load as the foam does not compress evenly. If the foam magically flattened and leveled structures I assure you me and anyone else who has framed a house would use it everywhere we needed level and flat surfaces.

Makes Sense

 

[raisedonnintendo]

I just wanna know where is everyone getting these tanks at are they custom made local tanks or has someone had a major companys tank mess up?

 

[crewdawg1981]

Mine is a Marineland.

 

[acroholic]

Any tank manufacturer is going to have tank failures, either from making them or the purchaser doing something wrong.

Also, some of the failures you hear about are from tanks that have been bought, sold, and moved a couple times. So every failure you hear about is not from a brand new tank.

Glasscages tanks are ragged on a lot about failing, but my 100 rimless cube has been chugging along for a couple years now.

 

[gmpolan]

Both of mine were previous members oceanics...one seal went and the other hair lined cracked near the bulkhead.

 

[markl]

jmaneyapanda;596132 wrote: wavemaking technology plays a role in it for sure, in my opinion.

+1

 

[dave green]

Does someone have a definitive on the wavemaking? I just bought a wave making station and I'm planning to put it into the tank today or tomorrow...

 

[acroholic]

Website Dave;596282 wrote: Does someone have a definitive on the wavemaking? I just bought a wave making station and I'm planning to put it into the tank today or tomorrow...

Wavemaking affecting the lifespans of tanks is one of those anecdotal things that is probably true, but to my knowledge has not been proven scientifically.

EcoTech warns about wavemaking with Vortechs possibly affecting tank structure integrity in their MP60, 40,10 Pump Owner's Manuals, basically taking no responsibility if it happens.

It's a choice, really. No matter what waves you make, etc, a tank is 5 pieces of glass (acrylic) held together by silicone (solvent). There is always a chance something like this could happen. One reason I only buy new tanks.

 

[crewdawg1981]

Acroholic;596290 wrote: Wavemaking affecting the lifespans of tanks is one of those anecdotal things that is probably true, but to my knowledge has not been proven scientifically.

It's a choice, really. No matter what waves you make, etc, a tank is 5 pieces of glass (acrylic) held together by silicone (solvent). There is always a chance something like this could happen. One reason I only buy new tanks.

Agreed... its why I bought a new tank myself. :confused2:

 

[thbrewst]

I have a magnet scraper (Hammerhead) and it is strong enough to allow me to move around the corners without releasing the magnets. I have always wondered if this 'scraping' across the seal would be a bad idea. Is it? Should I stop this practice?

BTW, I think I am in the worst case scenario based on the above descriptions...I have a 175 bowfront, Oceanic, that was purchased used. Should I go ahead and call my insurance company about the impending damage? I did go out of my way to make sure that it was as level as humanly possible before adding water.

 

[ichthyoid]

Dow-Corning used to offer a 'lifetime' warranty, as I recall. Perhaps there is a reason they discontinued their brand.

 

[jamescook]

My Clarity Plus brand had a lifetime warranty too, but I'm still waiting for that new one!

 

[rbredding]

SuperClown;596118 wrote: I know that people use the term gravity when measuring salinity may be a stupid question but does salt water create more outward pressure in a tank than fresh water?

YES...


Just as filling your aquarium with DIRT would create more lateral force (or outward pressure as you called it) on the tank..

The heavier the substance within a confined space, like an aquarium, the greater the pressure "pushing outward" along the bottom joints..

 

[fish scales2]

I would like to add:

If a tank is glued and then is left in a position that is not 100% flat and allowed to cure in that position. (slightly twisted) It will fail prematurely.

On my larger tanks I have been gluing them together on there permanent stand and then allowing them to cure in place.

Here is an example of how to not water test a tank.

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<fieldset class="gc-fieldset">
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[grouper therapy]

Fish Scales2;596400 wrote: I would like to add:

If a tank is glued and then is left in a position that is not 100% flat and allowed to cure in that position. (slightly twisted) It will fail prematurely.

On my larger tanks I have been gluing them together on there permanent stand and then allowing them to cure in place.

Here is an example of how to not water test a tank.

///Users/newuser/Desktop/IMG_1801.jpg alt="" />///Users/newuser/Desktop/IMG_1801.jpg alt="" />
///Users/newuser/Library/Caches/TemporaryItems/moz-screenshot.png alt="" />///Users/newuser/Library/Caches/TemporaryItems/moz-screenshot-1.png alt="" />///Users/newuser/Library/Caches/TemporaryItems/moz-screenshot-2.png alt="" />

Excellent Idea!!!:thumbs::thumbs::thumbs::thumbs::thumbs: And thank you for using the term FLAT

 

[ichthyoid]

grouper therapy;596404 wrote: Excellent Idea!!!:thumbs::thumbs::thumbs::thumbs::thumbs: And thank you for using the term <u>FLAT</u>

I mistakenly used the term level above alone. Thanks for the edification.

A tank support should be both flat and level for uniform distribution of the mass.

 

[raisedonnintendo]

ichthyoid;596217 wrote: This is one time we may</em> not agree. If a tanks not level to begin with, a layer of foam may not be able to correct the offset. However, 'compliant' (ie-to have 'give') foundations help distribute uneven forces. It is a fundamental engineering technique. I have used foam by itself on smaller glass tanks, and 'sandwiched' between layers of plywood on larger ones. I also extend the foam beyond the edge of the tank frame, as this eliminates 'rolling'.

On the other hand, my O'Dell 55 sat for 30 years with nothing but 1/2 inch plywood under it. It should also be noted that plywood itself has some degree of compliance, as well. I am not a fan of 'chip board' for supporting a tank, either.

They just don't make things like they used to!

One of the reasons that silicone rubber adhesives work so well is that they are highly compliant materials, whereas glass is not.

FWIW- 'glass' is not a solid at all, but a highly viscous liquid. I know, that's hard to imagine but true. This was discovered when panes of stained glass windows from middle age's era cathedrals were found to be thicker at the bottom, than the top. This showed that they had 'flowed' downward from the effect of gravity over hundreds of years. This has since been shown to be fact via modern rheological testing, x-ray anlysis, etc. Metal impurities may be added to glass to form 'Crystal', which IS a solid.

The problem with glass is when you have a significant change in force over a small area. You may call it concentrated force if that helps envision it, but in the end that condition creates 'shear'. Shear forces are the enemy of high modulus materials, which include both glass and plastic (acrylic) tanks.

Panels of acrylic or glass detaching/leaking are an <u>adhesion failure</u>-IMO. This result may have been agrivated by shear forces, but in the end the 'joint' failed, NOT the core/'bulk' of the material itself. Material 'bulk' failures are usually more 'catastophic' in their manner of failure (cracks, breakage and shattering). Of course if the entire perimeter of the joint fails and the panel hits the floor and shatters, it would be difficult to assess the mode of failure without a microscopic evaluation of the joint portions. In the end, a good material analysis will reveal 'the smoking gun'. -JMHO

:doh: ok so i know you mean well so. i believe you may be mistaken. glass as in fish tank at room tempature does not have enough kinetic energy to overcome the energy barriers requires for movement of molecules past one another. also known as a solid it doesnt form crystals but doesnt move either to much friction. heres an easy one for you to understand. can you pour a bowl full of glass at ambient temp?as far as the old windowpanes glass made during that time was made thru the crown glass process. in often laid out rolled flat and even giving a spin. all causeing it to be thick at the the ends. the heavy end was usualy placed on the bottom. although some old windowpanes have that extra thickness at the top. funny enough it was taught in our metallurgy class in college. it was one of our Urban legends we learned about,that and also fools gold. i hope i have helped to further educate you and help you grow :up: