There's no film as far as I can tell. I have Water Sprite on order from the LFS, but it hasn't come in yet. I am getting impatient though...... and may go somewhere else.... I wonder, do pond suppliers carry water sprite??
I have never gone without live plants in my tanks before, and I think they are a great thing.. It seems as though I really never had a problem with ammonia and nitrites when I had live plants in my tanks.
It just seems that in this tank, there is alot of water movement from the filter (eclipse filter) on one side of the tank and I have an aerator stone on the other side, and there is no happy calm place other than the corner of the tank near the heater and filter intake tube for him to hang out.