Have been using my system for about 12 months and the flow rate has slowed down considerably. Do I need to replace the filters? Why has this slowed down? Do i need to clean them maybe?

No need to change the filters. Unlike other filtration elements, the Black Berkey filters are cleanable and should be cleaned every 12 months and Re Primed.. What typically causes the filters to drip slowly is turbidity and sediment clogging the micro-pores of the elements. Simply remove the elements from your system, and clean the Black Berkey element by scrubbing the exterior of each element under medium hot running water with a Berkey Brush cleaner or a Dishwasher brush or toothpaste.  (medium hard)   It’s simple to do and takes less than a minute per element.   Just scrum them pretty hard and make sure you scrum all sides of the filters and then Re prime and set up again. 

Do this every 12 months. 

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