I have a penguin 170 and a cascade 200 for my 55 gallon aquarium, is this enough filtration? I have 3 blood parrots, 5 headilght taillights, 6 guppies, 5 cories, 1 octinclins. Is my tank overstocked? If not does anyone have any suggestions on fish i could add? I also have a few plants that cover about 30% of my tank.