I have a questions about Hydroton (leca), the clay ball substrate.

1.) How heavy are they? Example: covering an average 10 gallon tank w/ an inch of the clay balls. 10 oz? 10 pounds?

2.) Over time, will they eventually form into a solid brick later on down the road?

3.) Over time, will they become brittle and break-off into little pieces?

Just curious. I'm looking at alternatives. I may have found one.

Thank you for your attention.
Brian