I found an unused (but 25 year old) vortex diatom filter in my parents garage rafters and I'm hoping to use it to polish the water in my 125g, however neither me nor my father have used a diatom in 25 years and don't remember how to use or maintain the filter. Any directions as to how to use the filter and clean it after use will be greatly appreciated. Also this filter was purchased for a 20g, but since it will be used only as needed I was thinking that I can simply run it a lot longer and it should be fine any thoughts on this?