Is there a benefit to providing sand and gravel in substrate if it isn't a DSB?

I was wondering if anyone has tried a 2" layer in the tank with 1" of sand and 1" or crushed coral/aragonite. I'm debating how to do the substrate right now. I'm convinced I don't want to do a DSB with or without plenum, but I don't want to limit my inhabitants with just one type of substrate or the other. Make sense?

 

Chances are in time it will all get mixed into one inseparable bed that will be a combo of crushed coral and sand and your inhabits will be limited to those who dont need fine sand

 

+1

While some burrowers would simply line the entrance to their dens with the larger pieces, sand sifters would have a rough go at it. Is their a reason you want to mix them? Most subsurface creatures prefer sand, and you can certainly have a 1 - 2-inch sandbed.

 

I've always done a 'nonsand' in every tank I've ever had, freshwater or salt. I'm a little worried that there may be issues I haven't dealt with before regarding sand and I'm hesitant.

My fish have always messed with the substrate to clear a spot downtown the glass. Will sand stir up and cause a mess when they do this?

Does sand, once it is 'live', provide filtering qualities the way crushed coral does or does it just provide a place for small essential creatures to live?

I'm building a 90 gallon and am overwhelmed with all of the decisions. This is just one of them.

 

I now prefer bare bottom to substrate tanks, but my experience, and I think the consensus, is that crushed coral provides roughly the opposite of filtration. It's a trap for waste and a nitrate factory.

I'm no expert on why sand doesn't do this, but I'll never use crushed coral again.

 

Sand provides a ton of filtration IMO. I have all kinds of works and pods living in my sand that are an essentially part of my clean up crew. If you want both, but the crushed coral in your sump

 

Now I think we are on to something. Sand bottom and more in the sump later if I don't like it.

Thanks.

 

I would stay away from crushed coral, ive seen lines and everything in my fine sand from worms and pods, plus there are plenty of hiding spots in the tock. Crushed coral keeps detritus held down in nooks and crannys making it difficult to get it to the mechanical filtration.

 

In agreement with everyone saying to stay away from crushed coral,it's a detritus trap,i've also mixed the two before in an older tank,ALL the sand eventually sifted to the bottom leaving all the crushed coral as a top layer giving my sand dwellers a hard way to go as well.

 

Is there a size of sand grain that is too large for sand sifting gobies?

Caribsea makes an aragonite pink that looks like it is larger size than a fine grain but I'm sure there is a limit to the size for sifters.