What do you rest your big rocks on?

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HarleyK

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Howdy

I’m converting my bare bottom tank to substrate and want to use a cushion for large rocks so that they don’t create direct pressure points on the glass. I don’t want to rest them on top of sand because I don’t want fish to dig underneath them.

Back in the day we used egg crate from the lighting section.
Just curious if there are other approaches.

Thx
HarleyK
 
I have used thin foam sill sealer material that is normally used in house construction though it usually only comes in blue or pink. ?

You could also use Dow XPS extruded foam board or similar products though the thickness may be an issue for appearances sake.

If you have fish that may chew on stuff, consider getting some cheap polypropylene cutting boards as they come in different thicknesses and colors.
 
I believe RD. RD. used large rocks before and had them sitting directly on the glass if my memory is correct.
 
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No need for anything. Add boulders, then add sand. Fish that dig won't cause any issues. The trick is using boulders/rocks large enough that they can't be easily moved by the fish, and they are flat enough on one side that they won't fall over. Flat rocks create zero pressure points, and the weight is distributed by the glass

. Egg crate does nothing, but possibly prevent a rock from hitting bare glass if the rock gets knocked over. It doesn't do anything if the rock falls and hits the back, front, or sides. So? I have used boulders in the 30-40lb range in my 125. 200+ lbs in total, and many of the fish were diggers. No problem. See below.

Being an all male set up this tank evolved & changed over the years as trouble makers got shifted elsewhere, but this is what the tank looked like early on. There was over 200 lbs of granite boulders in there.


View attachment 1367233
 
Maybe put a patch of silicone on the bottom of the rock where it meets the bottom of the tank and let the silicone dry before putting the rock in the tank? Just to add a little cushion, not to glue it into the tank. Of course this would pretty much preclude rolling the rock over if you wanted to expose a different side.

Just a thought...
 
Too late for me to edit but I also have used nothing under large rocks and large rock piles with no issues.

Just have a good grip on the rocks as you are lowering into the tank so you don't drop them. ?
 
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If one wanted to then if a rock was tall enough and the substrate was deep enough then one could use multiple pieces of egg crate with a hole cut out in the middle of them stacked on top of one another to form a type of crate for it without the eggcrate being seen.
 
If one wanted to then if a rock was tall enough and the substrate was deep enough then one could use multiple pieces of egg crate with a hole cut out in the middle of them stacked on top of one another to form a type of crate for it without the eggcrate being seen.


And the purpose of that would be? Not to mention, doing so would require a rather hefty amount of sand, which I have personally never been a big advocate of. At least not in freshwater systems.

Most landscaping yards will let you pick through their rocks, and finding smooth flat bottom rocks in various types/shapes/sizes is not that difficult. It's also relatively cheap.
 
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And the purpose of that would be? Not to mention, doing so would require a rather hefty amount of sand, which I have personally never been a big advocate of. At least not in freshwater systems.
My idea was for those that had to have a very specific look in their tank, the aquascapers, and had vertical space. Would I personally do this? No. It was just a thought I had.
 
Glad that memory hasn't completely faded, yet. lol And yes, Dee, I recalled you mentioning that in the past as well.

 
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