Trying to get a near to self sustaining tank is a challenge, and truth be known probably impossible.
However I understand there are things you can do to help out. So I bought 10 Amano Shrimp to set about cleaning up certain algae, and wasted food and detritus.
The side affect is that they are fascinating to watch. Have little characters of there own and sometimes are seen whizzing around the tank.
They also seem to be shedding the exo-skeletons every so often which is a good sign as they are growing. So a good addition.