carbonation drops, two of to every bottle 25oz. I wondered if you can add more yeast at bottling. Or if I added more primer. Previous batch was good on 2per. There are plenty of variables. I got a couple I want to look at. Using coopers yeast. Bottles and glass cleaning with dish detergent no good? Rinse a lot. sanitized. Leaves a film or some thing? Bottles are PET. Temp control. I'm holding them in range for the yeast 20-24C but its easier to do on the low side slowing things. Just be patient. Do nothing more. Every brew does it's own thing in it's own time. Stop thinking.