Illness to wellness. Good you are back on track, in full health, Paul. Stay healthy!
Changing the liner also will mean starting the pond anew as the ecosystem will get altered. My pond took about 8 months to 'settle' when I started. The slight unevenness of the surface caused by the woven fabric is just enough for the fine root to take grip when it touches it and instead of turning it enters. Of course, I do keep some areas open for the fish. There will be open areas between the lily leaves also.
