one way air lock didnt seal . should i worry?

What do you mean by it didn't seal?

 

More details would certainly help.

When did you catch the leak? If in primary (also called active), you'll have positive pressure with CO2 production and being heaver than O2, the CO2 will create protecting blanket for the beer. So unless a gaping open, risk is very minimal. However, if you caught the leak in secondary (also called conditioning), you've got greater risk.

No matter, I would not panic, just let it ride. It's part of being a newbie, but more of the time any worries you may have seem to work out just fine in the end.

 

What fermenter type do you use ?

 

did you put water in it?

 

Was your bung wet? They slip out if they are

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