You have a lot of fish in there. What kind of filtration do you have? How many of each fish do you have in the tank?
Silver sharks (Bala Sharks) need a group of 5+
Clown loaches need a group of 5+
Black widow tetras and the mollys could become food for the sharks, particularly once they get older.
What kind of Gourami?
What kind of Pleco?
You really should stop adding fish and look at the ones you have, some should be re-homed or given a larger tank.