As long as there's no overdose of CO2, the shrimps should be OK. Any yeast setup for CO2 CAN NEVER OVERDOSE on CO2, so its a non issue. Anyway for precaution,should you see your all shrimps and fishes starts to climb up the tank and staying there, then it means that there's insufficient O2 and the way to treat this to put in an airstone to oxidize, but then again,never come across this scenario in yeast CO2.

KG

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