Egg Crate Tank Bottom

[jcook54]

I'm setting up a small tank and I've heard/seen a lot of folks putting down a layer of egg crate (plastic light diffuser) as the very bottom layer before sitting in rocks and adding sand. It's been almost 15 years since I've setup a tank with sand and I'm curious why folks do this. I assume it's to protect the glass bottom from any falling rocks but it seems like the sand would do a pretty good job of that. If you added a layer of egg crate on your build, why? Does tank size change the calculus at all? I'm setting up a 20g IM AIO and there's won't be a whole lot of rock work in it regardless.

 

[ichthyoid]

Supports the rock, prevents settling & especially pistol shrimps, gobies, etc. from tunneling under & destabilizing things.

 

[Steve Burton]

I have no research to back this up but my thoughts are that it would be a bad idea due to detritus trapping. Some certainly makes its way below the top layer of sand, and egg crate would make it much more difficult for conchs, nassarius and other sand cleaners to get to, as they would have to access each individual square. When I set my tanks up I place the rocks on the bottom, then the sand so they do not drop due to tunneling critters. Any stacked rocks then have the sand to protect the bottom in case of falling.

 

[timeconsumer]

I originally did it on my mantis tank in case it decided to burrow and smash glass. Then when I saw the size of the mantis I laughed and took it out.

 

[Doberman13]

When I set up my first tank I looked through all the forums and read a lot of arguments for and against. I decided not to use the eggcrate because quite a few posts mentioned detritus trapping. There was one person who used thin plastic cutting boards siliconed to the bottom of the tank, then stacked rocks and sand on top.
If I ever do a bare bottom tank I'll be tempted to order sand colored cutting boards.

I would love to hear from someone who used eggcrate and has had their tank setup for 7+ years.

 

[Eric_n_Ga]

Litter box imo

 

[jcook54]

Supports the rock, prevents settling & especially pistol shrimps, gobies, etc. from tunneling under & destabilizing things.

I was looking to mitigate this by placing the rocks directly on the bottom before I added any sand. There's always going to be some risk that the rocks could shift but a good stable structure directly on the tank bottom is how I've dealt with this in the past. As far as it being a detritus trap, I think sand does a pretty good job all by itself. I suppose if you had a handful of critter that lived in and stirred up the sand they might avoid the little squares?

 

[Eric_n_Ga]

I would think of it like a gold sluce . Things tend to work their way down .

I took my rock , added epoxy where it hits the tank smooshed it flat and let it dry . Like feet . My center rock I drilled and put 1/2" acrylic rods and elevated it above the sand ,you could do that and have it at the sand bed level.