The answer is in the FAQ sticky
This is just a quick overview.
For most brews a secondary is not obligitory
The fermenting should take place in the fermenter (Primary).
After the fermentation is finished then it can be transferred to a conditioning/clearing vessel (Secondary). Secondary fermentation vessels are sometimes used when adding fruit after the primary fermentation.
When should this happen?
Fermentation can take any where from 12 hours to 3 months (and more) most "normal" brews would be done in 3 to 10 days. The hydrometer will tell you.
If you want to guess then there are other methods. The one that can not be relied on is the bubbles stop.
Experienced brewers decide themselves when to move and what to do. Every beer is different.
If you are not sure and want an easy rule of thumb for a normal beer then a lot of brewers are happy to stick follow the 1-2-3 rule. 1 week to ferment - 2 weeks clearing/conditioning - 3 weeks to bottle condition.
Other brewers are just happy to leave it in primary for and extended time until it is ready to keg or bottle.
Sometimes the "Secondary" vessel is called a bright or clearing tank
Hope that helps.
This is just a quick overview.
For most brews a secondary is not obligitory
The fermenting should take place in the fermenter (Primary).
After the fermentation is finished then it can be transferred to a conditioning/clearing vessel (Secondary). Secondary fermentation vessels are sometimes used when adding fruit after the primary fermentation.
When should this happen?
Fermentation can take any where from 12 hours to 3 months (and more) most "normal" brews would be done in 3 to 10 days. The hydrometer will tell you.
If you want to guess then there are other methods. The one that can not be relied on is the bubbles stop.
Experienced brewers decide themselves when to move and what to do. Every beer is different.
If you are not sure and want an easy rule of thumb for a normal beer then a lot of brewers are happy to stick follow the 1-2-3 rule. 1 week to ferment - 2 weeks clearing/conditioning - 3 weeks to bottle condition.
Other brewers are just happy to leave it in primary for and extended time until it is ready to keg or bottle.
Sometimes the "Secondary" vessel is called a bright or clearing tank
Hope that helps.