Filter Floss in a Substrate layer?

[O13SC3N3]

Why? Wouldn't that cause rooters be like impossible to pull and replant? Any other specific reason? I keep seeing videos of people putting poly fill and filter pads under substrate, with no reason as to why. Is there any real benefit to this?

Edited January 4, 2021 by O13SC3N3

[gardenman]

CaribSea makes a Rhyzomat for planted aquariums that's designed specifically for plants. The negatives you cite "making plants impossible to pull and replant" is the benefit of it. Lots of people have problems with plants coming unplanted and floating. By putting something like a Rhyzomat or poly fill under the gravel, you give the roots something to grab hold of and to help keep them in place. Once the roots penetrate the poly fill or Rhyzomat, they anchor the plant in place and make it hard for a fish to uproot it.  I've seen big cory cats uproot a plant to try and get some speck of food they think is hiding under it. If you prefer a sand substrate and use fine sand, keeping plants planted can be a real challenge. A layer of poly fill or something like the Rhyzomat makes that possible. Once the plants get their roots in that layer, they're pretty much glued there and no matter how hard a cory or other fish tries to dislodge them, they can't. 

[O13SC3N3]

Ok ty!