I'm posting this in both the saltwater and freshwater sections because I don't know who would be more likely to know the answer.
So there's substrate out there for reptile tanks that's called calci-sand and it's calcium carbonate. I found a page online about the dangers of over exposure harming reptiles and humans, but what about fish? I mean, there's lots of things we put in tanks that can be dangerous to us (the first that came to mind is just about every ich medication that's known to the state of california to cause cancer). So would calcium carbonate in your tank hurt your fish? Here's the link to the page on the dangers: Calcium Sand - Dangers
So, assuming all of this is null and void because it's in a fish tank (which doesn't make a lot of sense but also wouldn't surprise me), what effect would this have on the water chemistry? Does anyone know if it would affect the amount of calcium or the pH or something in the tank?
I asked my friend and she said she had no idea about the water chemistry but when this stuff gets wet it hardens almost to a cement. If THAT is also true, what would happen if you used it like sand in your tank, stuck some plastic plants in it, and then filled it with water? Would it give you a solid substrate to hold plants in place and you wouldn't have to clean it? I know a lot of beneficial bacteria lives in the gravel/sand, but maybe a thin layer underneath would hold down your plants so your big fish (i.e. SA cichlids) couldn't "redecorate"?
I know you don't really use plants in saltwater but I figure someone out there might know about the calcium and all that, since obviously I don't.
(Sorry there's like three different questions, I was thinking really deeply into this)