I am using a over flow sump pump at the bottom of my aquarium. My sump pump got 3 compartment which is 1st compartment is sponge filter, 2nd is bio ring and 3rd is uv lights filter. Just now i notice snails at the sump pump filter. I already soaked all the filter(sponge and bio ring) with boiled water. Anythings else i can do to solve the problem and the snails wont come again. Thanks you in advance for all the advice.