I know I have the tank overstocked. I have 1 oscar 9", 2-red parrots(Im not really into hybreads but my brother bought therm) 1-Jack dempsey 6" , 2-electric yellow ciclids 3" , 1 6"ciclid, and 4-6 ciclid under 4" wich I dont know what type they are. I had to put a devider up and keep the oscar and 2 other large ciclids on one half. Some of my fish started dissapearing. I have another 75 gal That Im going to set up for the larger ones, and a 125 being set up for saltwater. I dont think I need to do more water changes. I have a wet/dry for a 300gal the water goes through 3 12"/12" media bags before the media balls. I have a 1,400 gph pump. Theres also a protien skimmer built in the wet/dry. , And I clean the tank weekly doing at least 25-30% water change. The tank is totally overfiltered and crystal clear. It is overstocked-but Im working on that. I want to run all my freshwatr tanks through one large filtraion setup in the basement then use a large pond pump to pump the water back upstairs to the tanks. Im hoping that will cutdown on the noise. The 90 gal i have the ciclids in is completly set up for saltwater. I just cant afford all the live rock and fish right now. I will try to post some pictures today. I lent out my camera and Im waiting for it. Hopefully someone can help identify what type of ciclids they all are.