You can try adding some bacteria. You can get it at a store that carries pond supplies. The bacteria help to clear up the waste quicker. It keeps my tank nice and clean between cleanings. In fact, once the bacteria becomes established, I mostly just have to clean the filter.
-----
0.1.0 ornate box turtle
1.0.0 eastern box turtle
1.0.0 Yellow belly slider
0.1.0 Red belly cooter
0.1.0 Australian shepard
1.11.0 chickens
1.0.0 Dutch(rabbit)
3.2.0 children (do I still count the married ones?)
1.0.0 husband