I'm really sorry to tell you your tank is seriously overstocked.
Bala sharks are schooling fish and do better in groups of three or more and grow to be about 10 inches. Here are the recommendations for bala sharks.
http://www.liveaquaria.com/product/p...fm?pCatId=1177
Pictus cats need lots of hiding places(rocks,
driftwood, plants) to feel safe. It also gets to about 10 inches. Here are recommenadations for them.
http://www.liveaquaria.com/product/p...cfm?pCatId=933
Your plec is probably a common plec. and they can get over 12 inches.
So as you see you are going to need a much larger tank to keep these beautiful happy and healthy.
By all means leave all th hiding places you have,The majority of the fish in that tank are bottom dwellers and need hiding places.
Carol