The in-laws are replacing their ceramic tile & I was looking at a pile of it thinking it would be good cover for FH minnows, fry etc. Would this be OK to use in a new pond? Also what about using old pieces of carpet, maybe rolled up or with a hole in the center then slid over some vertical standing PVC pipe to create some cover? Just trying to brainstorm a little while I'm looking around at some of the in-laws "trash".