City have scored 22 goals in their past four home games but there were defensive concerns in the 4-2 Champions League win over Viktoria Plzen on Wednesday night.
In each of the last three Premier League campaigns, no other side have conceded fewer top-flight goals than City.
But, with inspirational captain and centre-back Vincent Kompany having been injured for some time, there have been some defensive struggles.
Richards is well aware of that fact and the City defender said: "We are playing some great stuff - at the weekend against Tottenham (a 6-0 top-flight home win on Sunday) we were outstanding.
"But we have just got to sort out the goals against now.
"We want more clean sheets. In the last three years we have had the best defence.
"We have been a bit shaky this season but hopefully we can put that right now."
City qualified for the Champions League knockout stages before Wednesday's game but must better the 3-1 win Bayern Munich inflicted on them in Manchester when the teams meet on December 10 in Germany in order to go through as group winners.
Richards admits that will be a tall order but has promised an attacking outlook.
"The match against Bayern is going to be a tough game," he said. "They are a strong team. If we win we could top the group but it is going to be very hard to go to their place and win.
"They have got special players there and, in my opinion, they are the best team in the world.
"I think we have got to be careful in defence but we have got to go and attack because we have got to win. It will be a good game."