[marshmallow]

I really love the way coral/shell substrate looks but am getting the impression that it would be difficult to grow plants in it. Opinions?

 

[Blue Ridge Reef]

It's going to skyrocket your pH and KH. Not ideal for most plants or freshwater fauna (African rift lake cichlids and a few other exceptions apply). I had an African planted tank for several years and a few things did quite well in it, but I have far better luck using water on the soft side.

 

[rzn7z7]

Crushed coral is primarily CaCO3, yes? I think that'll raise your KH and the affect of KH on plants is best described here

2HRAquarist

Large water changes of low/no KH water would help

 

[Blue Ridge Reef]

Large water changes of low/no KH water would help

Issue there is wildly swinging parameters each water change. For plants only, that would likely be tolerated but few fauna suffer that well.

 

[somewhatshocked]

Could always go the lighter sand/gravel route with lots of coated shell pieces mixed in. That would provide a similar aesthetic without the water parameter shenanigans.

There are tons of cheap shell options online for buying in bulk. Even tiny spiral ones like ceriths that would look nice without being crushed. May not even impact water parameters.