i have a fluval 305 an its been giving me a bit of troubles for about a month now when i pump it to get it goin decent after a few mins it used to slow down to a trickle so i bought new lines they are as short as can be the fluval pump is directly under the tankbut now its runnin good then trickling is there any other kind of maintenance i should be looking at even when i rinse all the filter gear inside the 305 it stil does the same thing i only rinse the filter gear an inside the resivoir am i missing anything? its a heavily populated 55 gal i also run a fluval u2 to help out my issue but i need my u2 back in the other tank