^ Thats mfk here for ya. Some will be helpful others will not be. Well i just recently purchased 2 of these bad boys for my 210/225 gallon tank. So let me tell you my experience with the fx5. Let me say that you don't need to use that prefilter media as i think its a waste of money and space your fx5. Your going to need 2 fluval boxes of the bio-max to fill one tray. They are 500 grams/17.63 ounces per box. So depending on how much bio-logical filtration you want? 1tray = 2boxes 2 trays= 4 boxes. This will be your main bio-logical filtration. Next will be the Water Filter Polishing Pads, and the Fine Filter Pads for Fluval FX5 to maintain a crystal clear water, as this will be the main thing to trap all the micro particles and debris that cloudy up the water. Imo you don't need to buy this at all. You can find cheaper substitute for it. I sub it for pillow case stuffing and pot scrubbies. You adjust to your own liking per tray. Next i added Fluval Carbon, 100-gram Nylon Bags which comes 3 small bag per box. An empty tray could and almost likely fit 2 of these if you want to use them as they aid in keep the water clear. Hope that kind of help. I'm still learning this stuff myself. Hopefully someone with more knowledge than me will also give their input.
