Substrate Overhaul

[RaymondL]

Has anyone ever replaced their existing substrate complete or partially in an established tank with a different type?

Is this a forbidden practice in part or whole - for partial replacement, it's removing the top layer say quarter inch and putting in new substrate in its replacement.

Thanks

 

[tzabor10]

Having unmatched substrate can look uneven and spotty. You might also stir up too much detritus at once