just begun biocube 14g

[tammysocial]

Hello i bought me a 14g biocube tank from my friend. the tank has 15 ilbs of live rock maybe more. The tank had been setup for 2 years. only thing that was living in the tank was the rock. I have now but 5 snails, 5 crabs. can someone explain to me about taking the bioballs out now after all the years. My systems has the filter and bioballs just like you buy it plus a heater. do i need to buy a powerhead? I did not want stuff sticking out in the tank like pumps ,lines and hoses. I think this makes the tank look bad. what should i do from here? thanks