40 1 inch convicts and texas cichlids need a bare minimum 125 gallon for a couple months. I hope your not keeping ALL of them? Because that is a lot of cichlids to care for. To keep all of them at adult size, you would need a HUGE TANK.
Wow i couldnt imagine the aggression in that tank, maybe do 10 and 10 for 20. 40 fish will grow to 2 inches in 3 weeks that will double ur load. A pond would be a more accurate home for your suggested stock imo