Too many variables. How are you dosing CO2? Flow rates? Different methods are better at putting / removing CO2 than others. Bubble counters are different as well, so my 1 bps might be worth 2 or 3 on yours. Do you have a drop checker? You may just have to slowly raise the bubble count until you get where you need to be.
For example, I just swapped out my diffuser and stuck the end of the CO2 into the impeller on my pump. Much smaller bubbles. To make sure I don't overdo it since the CO2 delivery might be far more efficient I've dropped the bubble count a bit to compensate until I'm sure there's no danger and am slowly working my way back up. Every change you make may have dramatic effects and it's worth it to go slowly.
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