Gravel for Cephalotus top covering?

[twigs]

I really want to use white gravel as a top covering for Cephalotus. I know limestone and marble will leech minerals. I have found aquarium gravel that I like but it says it is coated in acrylic to make it inert. Is it ok to use coated gravel? Or is there another source for inert gravel?

 

[Nepenthes0260]

I used to use pea gravel for a topping for my cephs and pygmies. I found sillica sand works better and keeps down weeds more. I would guess aquarium gravel would work, too. I used to use aquarium gravel as a part in my nep mix.

 

[hcarlton]

I would avoid anything that has coatings or colors, and go for fully intert materials. Quartz gravel, silica sand (made of the same thing as quartz, just smaller particles) and thoroughly washed before applying would be far better.