During practices there are often no referees, so players will generally self-ref the games. It is great if teams can have referees in the water during their practices, but if not there are a few ways that teams can handle fouls.
The most common method is to allow all players to call any fouls they see, whether it is a foul that they were not involved in, one they committed, or one committed against them.
Another method is to only allow players to call fouls committed against them, or fouls they are not involved in. Not allowing players to call fouls they committed will allow the advantage rule to play out more frequently. A player that was fouled may decide to not call the foul if they think they didn't lose the advantage. This will reduce the number of stoppages.
The last method some teams use is to only allow players to call fouls they commit or fouls they are not involved in. This approach keeps the spirit of the game lighter and reduces the number of arguments about calls. Occasionally players foul without realizing it which is why players not engaged can still call fouls. This approach also reduces retaliatory and misjudged calls. Retaliatory fouls occur when players get a bit worked up during games, and call fouls against their opponents in retaliation. Also, often plays that are clean can feel like fouls to the player who loses the puck. Not allowing players to call fouls against opponents they are engaged with eliminates retaliatory fouls and misjudged fouls.
Each team has their own preferences as to how they self-ref during practices, and teams may have to try out a few methods to determine which one works the best for them.
Stopping play:
In general to stop the play during a practice, the player that wishes to stop the play will repeatedly hit their stick on the bottom of the pool, the gutter, their hand, or anything that will make noise until all players have stopped and surfaced.
SELF REFFING