Egg-crate under substrate to support large rocks?

[AdamS]

Is it recommended to put egg crate under your substrate to support large rocks or other higher weigh items?  Looking for thoughts from the internet.  I’ve placed it in some of my tanks and am turning up a few more tanks and wondering if it is worth while.  Thanks. 

[Cory]

How large? I've never done it since I was a new hobbyists like 18 years ago. I've done some pretty big rock stacks since then and have never had a problem.

[Chris]

I've never felt the need. 

Its a small hassle compared to cleaning up a tank off the floor. So if you're using lots of heavy rocks, might be worth it for piece of mind. 

[FishBagels]

Yes I’ve done it for a recent mbuna setup with heavy locally collected river rocks. 
 

might not need it but I personally wanted some peace of mind since my 55gallon tank was on the 2nd floor. 
 

use these as the cheapest and easiest solution. You can cut it with scissors down to size. 
 

https://www.homedepot.com/p/PLASKOLITE-4-ft-x-2-ft-Suspended-Egg-Crate-Light-Ceiling-Panel-1199233A/202025149?source=shoppingads&locale=en-US&pla&mtc=SHOPPING-CM-CML-GGL-D30-030_023_GLASS_SCREEN-NA-NA-NA-PMAX-5707970-NA-NA-NA-NBR-NA-NA-NEW-NA&cm_mmc=SHOPPING-CM-CML-GGL-D30-030_023_GLASS_SCREEN-NA-NA-NA-PMAX-5707970-NA-NA-NA-NBR-NA-NA-NEW-NA-71700000118585240--&gad_source=1&gbraid=0AAAAADq61UfrGh4ebjcd1xI54-DWj9IrM&gclid=Cj0KCQjw6PGxBhCVARIsAIumnWbrc-PG7mla76jHEic-Ffz8SiesnNT6GPdD1UVrwnKhDpVttEWmClsaApIaEALw_wcB&gclsrc=aw.ds

[doktor zhivago]

I was thinking actual egg packaging and I was so confused until the ceiling tiles got posted.....

[Sacah]

I think it also depends what your stand looks like, if it's a flat bit of wood you don't need to worry about distributing the weight beyond what your substrate would do. If your stand is largely hollow with a few bracing bars, then this could help move some of the weight towards one of the braces.

[AdamS]

I don’t have a particular rock or even a weight in mind, just curious if it was worth the effort or if the substrate would support the weight and I didn’t have to worry.

My stand just braces the outside of the tank bottom.  

[Tony s]

I found this fascinating, so I looked it up. a cubic foot of water weighs roughly 62 lbs. a cubic foot of rock weighs anywhere from 146 lbs to 186 lbs. I know the tanks are overbuilt to withstand extra pressure. but depending on the size of the rock stand, that's a lot of extra pressure. not to mention any hotspots from the rock edges.

[Sacah]

I looked up if I could find anything specific about the manufacturing of tanks, found a lot of references to people using tempered glass on the bottom that could handle at least 3 times the possible water weight, to account for substrate, decorations etc.

Then I found this video and the guy has 220 pounds in a 10 gallon tank, which apparently would hold 83 pounds of water, so that makes me feel better about putting rocks in mine (-:

 

[AdamS]

That is one way to test it out.  Thanks for finding that video!  That pretty much alleviates my concern. 
Anybody else up to standing in your aquarium and seeing if it holds you?

 

[Pepere]

On 5/9/2024 at 10:58 PM, Tony s said:

I found this fascinating, so I looked it up. a cubic foot of water weighs roughly 62 lbs. a cubic foot of rock weighs anywhere from 146 lbs to 186 lbs

It does bear mentioning though that the rock will displace water.  Ie if you add a cubic foot of rocks that have a density of 162 pounds per cubic foot, since you end up putting a cubic foot less of water, you are only adding 100 more pounds to the tank than if you had no rocks….

[Tony s]

On 5/10/2024 at 12:55 PM, Pepere said:

It does bear mentioning though that the rock will displace water

Quite correct, still a significant addition of weight. but if true that the tanks are designed to hold 3x the weight of water, it should be good. I worry more about the weight finding a hotspot. where the rock has a tiny protrusion and all of the weight gets concentrated into a point. Mostly I've seen rocks placed directly on glass, but if it makes a person more comfortable, I think It's just a matter of choice.

[johnnyxxl]

I put a layer of sand down then my rock etc then more sand and pea gravel 

[AdamS]

Nobody wants to take a video of them standing in their tank?

[Tony s]

I’ve seen people get inside of larger tanks and the tank doesn’t even notice. But even standing in a 75g the tank wouldn’t care. Assuming normal tanks have at least a 10 lb. Per gallon of water, easily. And learning of the potential 3x rating. To really test it out you’d have to stand on 1 foot. In a 10g. 🤣

[Katherine]

On 5/11/2024 at 8:17 AM, Tony s said:

To really test it out you’d have to stand on 1 foot. In a 10g. 🤣

I have an empty 10 gallon... What I do not have is cut resistant shoes. Think I'll pass.

[johnnyxxl]

On 5/11/2024 at 1:10 PM, Katherine said:

I have an empty 10 gallon... What I do not have is cut resistant shoes. Think I'll pass.

I suspect that the shoe's would be fine unless you are on the stand, but the potential mess, no thanks 

[AdamS]

That doesn’t sounds like a fun youtube video