"Dan" wrote in message
...
Thanks for the advice; I will try mineral oil and I think I can get by
with slowing the flow rate also.

Dan

Could the Mineral oil somehow get into the tank? I already have some kind of
oilly layer on my water that I think is from the regulator, I doubt it from
any of my plants?
Also, wouldnt Nick be correct, once you have your bubble rate dialed in,
even if all the water evaporates from the bubble counter what difference
does it make?
John