Join Date: Sep 2006
Location: Forest Hills, NY
Laterite is designed to enhance the plant hosting ability of plain gravel.
Flourite is designed to be a gravel optimized for plant hosting.
so if you already have plain gravel, logically you should get Laterite,
unless you are willing to replace your old gravel completely with Flourite.
To help you make a decision, consider the actual gravel grain size you currently use.
If it's all already over 6mm or 3/8", then you really should replace it all with Flourite.
If your gravel is under 6mm, then the grain size is already optimized for plants,
and simply adding Laterite might be a better option, and less disruptive to your tank cycle.