On the topic of prefilter sponges for HOB and canisters, I always had the mindset that it kept the junk in the tank and prevented the filter from doing its job, which is to suck up all the stuff. Also, I was told that it would decrease the effectiveness and strain the motor. I have only used them on my power heads or tanks with fry. I have seen some video and posts where folks swear by them and the benefit of added beneficial bacteria on the medium. Here is one I found interesting about optimizing your HOB in which prefilter sponges are an important step. Thoughts, opinions, experience? Also, if you use them, can you give recommendations, show pictures, etc?