When we lost a day of lab due to weather, this messed up the fermentation tubes to the point where we were not able to see whether or not the microbe...

When we lost a day of lab due to weather, this messed up the fermentation tubes to the point where we were not able to see whether or not the microbe was fermenting and producing gas. Please give a logical explanation why we were not able to see the gas bubbles in the durham tubes. I was thinking that maybe it could be something to due with chemistry. Please give me a couple of explanations. Thanks.