High density foam under rimless tank - load is uneven?

neuro · 01/08/2013, 11:22 AM

I ordered a piece of high density, closed cell, 3/4" foam. After putting it underneath my unfilled, rimless tank, i noticed that there is some space between the foam and the tank, on one edge. Almost as if the weight isn't bearing down on that one edge.

All other edges seem to be fine. I double checked and turned the tank around on the foam, and it's the same edge that has some space. I also turned the whole stand around to make sure it wasn't a matter of my uneven floor, and it's still the same edge that has space.

Maybe it's the foam padding itself? Maybe it's too thick? I'll try turning the foam padding itself to see if it makes any difference when I get home.

I'm not sure what to make of it. Should I wait and put some water in it?

Anyone have any experience with this?

C4rN4gE · 01/08/2013, 11:32 AM

The blue rmax board? In my opinion, that stuff is too stiff. I used some foam from Lowes that was real squishy and not as firm.

jgraz · 01/08/2013, 11:37 AM

Quote:

Originally Posted by C4rN4gE

The blue rmax board? In my opinion, that stuff is too stiff. I used some foam from Lowes that was real squishy and not as firm.

+1. You have the wrong stuff. You basically want styrofoam. I think it's expanded poly something or another. Lowes/HD will have it. It's white and when you cut it you will have all those little balls around. That's the stuff you want.

neuro · 01/08/2013, 11:45 AM

No this is not the blue max board.

I have read from numerous postings here that says the closed cell, high density foam is what i needed. That the squishy, foam isn't exactly what I should be looking for.

Can anyone confirm?

96slowbra · 01/08/2013, 11:51 AM

depends on the manufacturer. most seem to prefer the 3/4" to 1" white styrofoam from lowes or home depot.

NanoReefWanabe · 01/08/2013, 12:01 PM

the white stuff will hold water and likely promote mold growth once it gets wet, the pink closed cell stuff obviously cant absorb water and therefore will not be prone to mold growth...

i would use the 1/2" pink closed cell foam...

as for your original question about the foam being off...it very likely could be the foam that is off a touch. put a level across the foam and see if there is a gap still...i am not sure how this stuff is cut in the factory but you can bet they have a tolerance for thickness, could be as much as 1/8" i dont know...

neuro · 01/08/2013, 12:04 PM

Quote:

Originally Posted by NanoReefWanabe

the white stuff will hold water and likely promote mold growth once it gets wet, the pink closed cell stuff obviously cant absorb water and therefore will not be prone to mold growth...

i would use the 1/2" pink closed cell foam...

as for your original question about the foam being off...it very likely could be the foam that is off a touch. put a level across the foam and see if there is a gap still...i am not sure how this stuff is cut in the factory but you can bet they have a tolerance for thickness, could be as much as 1/8" i dont know...

Thanks NRW. I do think now it's the foam. It did look a little weird when it came out of the roll i purchased--one edge was more rounded than the others.

I saw in this thread about reefsaavy suggesting using the white or pink insulation foam @ home depot:

http://reefcentral.com/forums/showth...oam+under+tank

i'll go to home depot and pick up the 1/2" pink closed cell foam.

thanks all. I'll update this thread once I do get things up and running.

jgraz · 01/08/2013, 01:00 PM

I'll just throw this out there again. You need the white styrofoam. Thats all. Anything else will not compress properly and will cause stress points. You don't want that.
You want Expanded polystyrene(styrofoam) It will probably not have a foil coating. But hey its your tank.

NanoReefWanabe · 01/08/2013, 02:06 PM

Quote:

Originally Posted by jgraz

I'll just throw this out there again. You need the white styrofoam. Thats all. Anything else will not compress properly and will cause stress points. You don't want that.
You want Expanded polystyrene(styrofoam) It will probably not have a foil coating. But hey its your tank.

the white foam is NOT what you want to use...
A> it will hold water and moisture...if you can 100% guarantee you wont spill see points B,C,D, E & F.
B> it will compress and likely move under load (wave makers will cause the tank to move) the foam could easily become loaded and unloaded as the weight of the water moves from side to side, causing undue stress to the tank, plus it will squish the foam unevenly as the sides of the tank dip up and down by 1 or 2mm, this could lead to resonance (which the wave is already in, you dont want your tank to be in it as well)
C> the ONLY thing you are trying to alleviate by using foam is point loads created by grains of sand/ dust hair/etc that by be on the top of the stand transferred to the bottom of the tank...
D>you want the tank to be fully and evenly supported on the bottom, white styrofoam may have dense and less dense pockets in it...
E> 1/2" pink rigid insulation will not compress under the tank, leading to uneven support or voids caused by the tank rocking.
F> 1/2" pink rigid insulation will very easily give way to a nail pop, grain of sand piece of hair etc that may be on the top of the stand without effecting the tank in any way shape or form.

neuro · 01/08/2013, 02:50 PM

great responses, great discussion.

thank you!

Humu Humu · 01/08/2013, 06:53 PM

Just my 2 cents, but forget the foam. Place your stand on the floor and level it to the max (I use wood shims). Then place your empty tank on the stand and repeat. Then fill the tank 1/3 full and repeat again. Finally fill the tank and test.

jgraz · 01/09/2013, 06:02 AM

Quote:

Originally Posted by Humu Humu

Just my 2 cents, but forget the foam. Place your stand on the floor and level it to the max (I use wood shims). Then place your empty tank on the stand and repeat. Then fill the tank 1/3 full and repeat again. Finally fill the tank and test.

He said the tank is rimless. It will need something under it. But for the most part you are right.

By all means follow wannabes suggestions. Just do two things, get a extra tank to have as an emergency backup, and please send him a link to the thread you make to ask about splitting seals and cracked glass.

neuro · 01/09/2013, 10:51 AM

Quote:

Originally Posted by jgraz

He said the tank is rimless. It will need something under it. But for the most part you are right.

By all means follow wannabes suggestions. Just do two things, get a extra tank to have as an emergency backup, and please send him a link to the thread you make to ask about splitting seals and cracked glass.

I'd like to know what reference you have that mentions anything but white insulation foam would cause such a disaster? You seem to have a lot of experience.

jgraz · 01/09/2013, 11:29 AM

Unfortunatly I can't referance any article. If I still had my old rimless glass sump I'd show you what happens when you pump a rimless tank on top of rigid foam. Rigid foam is just that rigid, it will not give and won't conform to fill is points of stress. Think of it as a matress for your tank. If you lay down on a a piece of wood, you will feel points of pressure all around your body. You can also find gaps between your body and that wood. In those areas the body wants to bend to fill in the space but it can't, that causes stress in those areas. Now laydown on a foam mattress, as it compresses your entire body is touching it in every spot evening the load, relaxing stress points and easing pressure in other areas. The same goes for the tank, especially a tank that has no frame. That is why when you placed it on the stand you found gaps. if you would have filled it the gap would almost certinaly disappear. however the stress created would eventually lead to failure. The rigid insulation boards are very similar, while not a rigid as wood, it will also not compress it will mearly bend giving the illusion of conforming. The expanded polystyrene will do this. It will not make the tank shake, not even sure how this was even dreamed up. Yes it will compress and this is how it ensures that there is no stress points. Will it hold water? IDK but when is the last time your coffee cup leaked on you.
Here is a little discussion my local reef club had on this discussion recently
http://www.njreefers.org/showthread....highlight=foam

biocube14g · 01/09/2013, 12:59 PM

Could u do half inch rigid foam, and 1/4 inch polystyrene on top of the the rigid? The rigid would give it the support, and the soft will give it the natural adjustment/settlement that you want.

neuro · 01/09/2013, 01:22 PM

honestly i don't really care. i just want to make sure the foam doesn't screw me, and works for its intended purpose.

now i'm seriously confused. luckily the foam isn't expensive--just a pain in the *** to buy and carry back.

neuro · 01/09/2013, 05:20 PM

For those curious, I've emailed Mr. Aqua distributors myself and this is what htey had to say:

"
the white foam should be good to use, but I am afraid that it will absorb water, the black foam we use is rubber base and does not absorb water at all. we have the black material for smaller tanks, we are look into bring them for the 60g in the near future. Thank you

Sevenports, Inc.
12407 E. Slauson Av., Suite E
Whittier, CA 90606
"

They didn't explicitly say anything about pink foam. I've asked them to clarify pink foam usage.

neuro · 01/09/2013, 06:43 PM

Another response when I asked them to confirm about the pink foam:

"i believe the pink foam will absorb water, (not sure about that) try to use the polyurethane or rubber foam or the tank and at least 1/4" thinkness and able to hold the weight. Hopefully this will help. "

.. and after i sent them the link to the pink foam, this is what they had to say:

"you can give a try, that sounds pretty good. Thank you for sharing."

uncleof6 · 01/09/2013, 11:17 PM

I am wondering why no one has thought that maybe JUST MAYBE the stand is out of whack..........all the foam in world ain't gunna do a darn bit of good if the stand is out of whack.

I think the foam issue is solved, at least it seems so. What color do your prefer? Pink, white, or black? The big tanks I have built ~ 300 plus, and numerous smaller ones, go on white rigid foam. I don't see an issue with mildew, but then with me, the water goes inside the tank.

neuro · 01/09/2013, 11:27 PM

Thanks a lot uncle.

I did think of the stand being off whack, but on first impressions the stand appeared to be OK when I put the tank on it without foam. Everything "seemed" to be fine. I'm not sure how else I can test it besides using a level (which I did).

The floor itself is off kilter, and I would be putting in shims once I get everything setup and half filled with water.

I picked up the pink foam, and I am considering using that. However, I may swing by home depot again to pick up the white foam just incase I change my mind.

Thanks all

uncleof6 · 01/09/2013, 11:34 PM

Quote:

Originally Posted by jgraz

I'll just throw this out there again. You need the white styrofoam. Thats all. Anything else will not compress properly and will cause stress points. You don't want that.
You want Expanded polystyrene(styrofoam) It will probably not have a foil coating. But hey its your tank.

You would be surprised how little the rigid foam compresses--compression of the foam is actually not such a good thing. The weight of a rimless tank, is spread relatively evenly across the foam. You put a rimmed tank on foam, and you will see some unusual results.........including a destroyed bottom panel.

BossHoggin · 01/09/2013, 11:50 PM

I was in a very similar situation. I built a new stand for my 125 and moved the tank to a different spot in the house. Floor wasn't level, stand wobbled a bit, as did the tank on the stand. Put pink foam on the floor for the stand and sump to sit on. Put a thicker piece of lighter density foam between the tank and stand to be safe.

Jeff000 · 01/10/2013, 09:00 PM

Quote:

Originally Posted by uncleof6

I am wondering why no one has thought that maybe JUST MAYBE the stand is out of whack..........all the foam in world ain't gunna do a darn bit of good if the stand is out of whack.

I think the foam issue is solved, at least it seems so. What color do your prefer? Pink, white, or black? The big tanks I have built ~ 300 plus, and numerous smaller ones, go on white rigid foam. I don't see an issue with mildew, but then with me, the water goes inside the tank.

This.
You want high density foam. You are not using the foam to level the tank, you are avoiding point loading.

Also, FWIW the builder of my 330g tank said if I put anything besides high density foam (he referenced the purple or blue stuff) between the tank and the top of the stand he would not warranty the tank.

neuro · 01/10/2013, 11:20 PM

jeff000,

is your 330g rimless?

Quote:

Originally Posted by Jeff000

This.
You want high density foam. You are not using the foam to level the tank, you are avoiding point loading.

Also, FWIW the builder of my 330g tank said if I put anything besides high density foam (he referenced the purple or blue stuff) between the tank and the top of the stand he would not warranty the tank.

launchnukes · 01/11/2013, 06:02 AM

I'm currently having a rimless tank built. Yesterday I asked the tank builder what kind of foam to get and he said 3/4" pink foam from home depot

01/08/2013, 11:22 AM	#1
neuro the cat did it Join Date: Jul 2004 Location: bay area Posts: 976	High density foam under rimless tank - load is uneven? I ordered a piece of high density, closed cell, 3/4" foam. After putting it underneath my unfilled, rimless tank, i noticed that there is some space between the foam and the tank, on one edge. Almost as if the weight isn't bearing down on that one edge. All other edges seem to be fine. I double checked and turned the tank around on the foam, and it's the same edge that has some space. I also turned the whole stand around to make sure it wasn't a matter of my uneven floor, and it's still the same edge that has space. Maybe it's the foam padding itself? Maybe it's too thick? I'll try turning the foam padding itself to see if it makes any difference when I get home. I'm not sure what to make of it. Should I wait and put some water in it? Anyone have any experience with this?

01/09/2013, 12:59 PM	#15
biocube14g Registered Member Join Date: Aug 2012 Location: Templeton, CA Posts: 240	Could u do half inch rigid foam, and 1/4 inch polystyrene on top of the the rigid? The rigid would give it the support, and the soft will give it the natural adjustment/settlement that you want. __________________ "Just one day, the ocean will be dominated by clownfish, and you will no longer hear of a shark attack, but rather a clown attack!"- MYSELF Current Tank Info: JBJ 28 Nano Cube, 14k Metal Halides, UV Sterilizer, HOB Protein Skimmer, 30 Lbs LR Main display; 30 Lbs rubble in sump, 10 Gallon Sump, 2 Hydor Koralia 240's, RIO 2100 Return Pump

01/09/2013, 06:43 PM	#18
neuro the cat did it Join Date: Jul 2004 Location: bay area Posts: 976	Another response when I asked them to confirm about the pink foam: "i believe the pink foam will absorb water, (not sure about that) try to use the polyurethane or rubber foam or the tank and at least 1/4" thinkness and able to hold the weight. Hopefully this will help. " .. and after i sent them the link to the pink foam, this is what they had to say: "you can give a try, that sounds pretty good. Thank you for sharing." Last edited by neuro; 01/09/2013 at 07:06 PM.

01/09/2013, 11:17 PM	#19
uncleof6 Registered Member Join Date: Jul 2004 Location: AWOL Posts: 12,013	I am wondering why no one has thought that maybe JUST MAYBE the stand is out of whack..........all the foam in world ain't gunna do a darn bit of good if the stand is out of whack. I think the foam issue is solved, at least it seems so. What color do your prefer? Pink, white, or black? The big tanks I have built ~ 300 plus, and numerous smaller ones, go on white rigid foam. I don't see an issue with mildew, but then with me, the water goes inside the tank. __________________ "Things should be made as simple as possible, but not simpler." (oft attributed to Einstein; most likely paraphrasing by Roger Sessions; compactly articulates the principle of Occam's Razor) Current Tank Info: 325 6' wide Reef

01/09/2013, 11:50 PM	#22
BossHoggin Registered Member Join Date: Mar 2012 Location: Compton, CA Posts: 198	I was in a very similar situation. I built a new stand for my 125 and moved the tank to a different spot in the house. Floor wasn't level, stand wobbled a bit, as did the tank on the stand. Put pink foam on the floor for the stand and sump to sit on. Put a thicker piece of lighter density foam between the tank and stand to be safe. __________________ Josh 60B mixed reef w/ 33G sump/refugium 125G FOWLR w/ Eshopps R_300

01/08/2013, 11:32 AM	#2
C4rN4gE Registered Member Join Date: Jan 2012 Posts: 56	The blue rmax board? In my opinion, that stuff is too stiff. I used some foam from Lowes that was real squishy and not as firm.

01/08/2013, 11:45 AM	#4
neuro the cat did it Join Date: Jul 2004 Location: bay area Posts: 976	No this is not the blue max board. I have read from numerous postings here that says the closed cell, high density foam is what i needed. That the squishy, foam isn't exactly what I should be looking for. Can anyone confirm?

01/08/2013, 11:51 AM	#5
96slowbra Registered Member Join Date: Nov 2011 Location: utah Posts: 218	depends on the manufacturer. most seem to prefer the 3/4" to 1" white styrofoam from lowes or home depot.

01/08/2013, 12:01 PM	#6
NanoReefWanabe Registered Member Join Date: Oct 2006 Location: Barrie, Ontario, Canada Posts: 6,639	the white stuff will hold water and likely promote mold growth once it gets wet, the pink closed cell stuff obviously cant absorb water and therefore will not be prone to mold growth... i would use the 1/2" pink closed cell foam... as for your original question about the foam being off...it very likely could be the foam that is off a touch. put a level across the foam and see if there is a gap still...i am not sure how this stuff is cut in the factory but you can bet they have a tolerance for thickness, could be as much as 1/8" i dont know...

01/08/2013, 01:00 PM	#8
jgraz Registered Member Join Date: Oct 2011 Location: Bordentown, NJ Posts: 697	I'll just throw this out there again. You need the white styrofoam. Thats all. Anything else will not compress properly and will cause stress points. You don't want that. You want Expanded polystyrene(styrofoam) It will probably not have a foil coating. But hey its your tank.

01/08/2013, 02:50 PM	#10
neuro the cat did it Join Date: Jul 2004 Location: bay area Posts: 976	great responses, great discussion. thank you!

01/08/2013, 06:53 PM	#11
Humu Humu lost in the pelagic zone Join Date: Oct 2010 Location: Chicago Posts: 207	Just my 2 cents, but forget the foam. Place your stand on the floor and level it to the max (I use wood shims). Then place your empty tank on the stand and repeat. Then fill the tank 1/3 full and repeat again. Finally fill the tank and test.

01/09/2013, 11:29 AM	#14
jgraz Registered Member Join Date: Oct 2011 Location: Bordentown, NJ Posts: 697	Unfortunatly I can't referance any article. If I still had my old rimless glass sump I'd show you what happens when you pump a rimless tank on top of rigid foam. Rigid foam is just that rigid, it will not give and won't conform to fill is points of stress. Think of it as a matress for your tank. If you lay down on a a piece of wood, you will feel points of pressure all around your body. You can also find gaps between your body and that wood. In those areas the body wants to bend to fill in the space but it can't, that causes stress in those areas. Now laydown on a foam mattress, as it compresses your entire body is touching it in every spot evening the load, relaxing stress points and easing pressure in other areas. The same goes for the tank, especially a tank that has no frame. That is why when you placed it on the stand you found gaps. if you would have filled it the gap would almost certinaly disappear. however the stress created would eventually lead to failure. The rigid insulation boards are very similar, while not a rigid as wood, it will also not compress it will mearly bend giving the illusion of conforming. The expanded polystyrene will do this. It will not make the tank shake, not even sure how this was even dreamed up. Yes it will compress and this is how it ensures that there is no stress points. Will it hold water? IDK but when is the last time your coffee cup leaked on you. Here is a little discussion my local reef club had on this discussion recently http://www.njreefers.org/showthread....highlight=foam

01/09/2013, 01:22 PM	#16
neuro the cat did it Join Date: Jul 2004 Location: bay area Posts: 976	honestly i don't really care. i just want to make sure the foam doesn't screw me, and works for its intended purpose. now i'm seriously confused. luckily the foam isn't expensive--just a pain in the *** to buy and carry back.

01/09/2013, 05:20 PM	#17
neuro the cat did it Join Date: Jul 2004 Location: bay area Posts: 976	For those curious, I've emailed Mr. Aqua distributors myself and this is what htey had to say: " the white foam should be good to use, but I am afraid that it will absorb water, the black foam we use is rubber base and does not absorb water at all. we have the black material for smaller tanks, we are look into bring them for the 60g in the near future. Thank you Sevenports, Inc. 12407 E. Slauson Av., Suite E Whittier, CA 90606 " They didn't explicitly say anything about pink foam. I've asked them to clarify pink foam usage.

01/09/2013, 11:27 PM	#20
neuro the cat did it Join Date: Jul 2004 Location: bay area Posts: 976	Thanks a lot uncle. I did think of the stand being off whack, but on first impressions the stand appeared to be OK when I put the tank on it without foam. Everything "seemed" to be fine. I'm not sure how else I can test it besides using a level (which I did). The floor itself is off kilter, and I would be putting in shims once I get everything setup and half filled with water. I picked up the pink foam, and I am considering using that. However, I may swing by home depot again to pick up the white foam just incase I change my mind. Thanks all

01/11/2013, 06:02 AM	#25
launchnukes Registered Member Join Date: Mar 2009 Location: Vero Beach, FL Posts: 703	I'm currently having a rimless tank built. Yesterday I asked the tank builder what kind of foam to get and he said 3/4" pink foam from home depot __________________ Red Sea Reefer 750xxl Previous Tank: 300DD Display 500g system.