2nd Update: I've had this filter for just over a year and it still has the same quietness as day one. It is going strong and I haven't had to replace it or clean a motor or anything, besides pull out a few bits of duckweed that somehow got stuck around the outside. The flow has stayed the same which is crazy to me. I haven't even needed to buy a second as a backup. FYI, I also took a bit of a risk with buying this filter because not many reviews were out at the time (under 100 I think). Now it has 3000+, over the course of about a year. If you like good value and quietness, and don't mind appearance if you're doing something similar to my setup, then this is the one to buy.1st Update: I got this filter for Christmas and have used it for over three months now. It sounds the exact same as the first day I started it (really quiet).Original Review:My setup: 75 gallon fish tank that is stocked well (about 20-30 fish, I never know because some fish like to burrow and I don't see them for months but they always pop up alive and well out of nowhere). I use the 400GPH NO.17 filter and a piece of vinyl tubing from the filter into the back of a 75 gallon Marineland Penguin filter (that I don't use anymore) on the other side of the tank.I have bought the Tetra Whisper and Marineland Penguin filters in the past for this 75-gallon (283-liter) tank. Both of my 70-gallon tetra whispers lasted 5-7 months before failing completely. My 75-gallon marineland penguin has lasted the entire year and a half I've used it, but it's become very noisy. Note, I clean my filters and the motors regularly - especially if they become too loud. I have a tiny 10-gallon tetra filter that has lasted 5+ years and counting, so I know how to maintain filters. But for my 75-gallon tank, I've used three different filters. From what I can tell so far, this one will last quite a while because of how quiet it has stayed and how I haven't seen any reduction in flow.Things I like about this filter:- The value for money is SO GOOD.I got this at $23.99 and it is $22.99 at the time of this review (oh well, haha). This is compared to a 70-gallon Tetra Whisper at ~$35 and a 75-gallon Marineland Penguin at ~$50 (which I got it for less than $30 back in 2021). It has worked perfectly for my 75-gallon tank, albeit with my specific setup. But it is great value for a 75-gallon tank.- How quiet it isDisclaimer: I've only had this for three months now, but it is still so quiet that sometimes I don't even think it is on and I have to see if there is water flow (which there is a lot of). Keep in mind that mine is submerged about 6 inches beneath the water surface, 6 inches from the tank gravel, and it's up against glass.- Water flowBased on my experience, with a good setup (intake on one side of tank, output on other), and if you don't get a faulty one, this filter is good for up to 100 gallons or 380 liters, MAYBE more.I read the reviews on here before buying and I saw one that said they got the 400GPH filter and it wasn't enough for a 10-gallon? Maybe they got a faulty one, because mine is putting out about the same flow, if not more, as my 75-gallon marineland filter. My marineland would slow down flow over time until I cleaned it out, and it has wheel filters that would stop spinning altogether. This NO.17 filter, with a piece of vinyl tubing that goes into the back of the marineland, adds another step of filtration, AND it is at the opposite end of the tank so water circulation is 10 chef's kisses out of 10. Without the tubing, it'll produce decently high current in the tank. I don't want high current because my gouramis prefer low flow, so the tubing gives that added bonus. It might actually have more flow than the marineland because the filter wheels started spinning again. To clarify, I don't have the marineland running because the motor is too noisy.- Safety for fishI have some tiny fish in my 75-gallon, namely zebra + pearl danios and otocinclus catfish (you can see a small danio in one of the pictures). I haven't had any fish get stuck in the filter, and I don't see any spots where they even could get stuck. If I had shrimp, snails, baby fish, or nano fish, I would worry about them getting into this filter.My advice:If you are using this filter (or most filters) with smaller fish, shrimp, snails, etc., then buy a fine mesh filter bag (something like this: https://a.co/d/1LUrOT3) and cover the intake of the filter. I use one in my 10-gallon tank that covers the intake of a 10-gallon tetra whisper filter. I got my filter bag at petco, but they might be at petsmart too.If you're thinking of using tubing with this filter, take the tubing attachments (one is small, the other larger) and take them to a Home Depot or Lowe's and try out different tubing sizes until you find one that fits. I found the larger one is good for tubing with an inner diameter (ID) of 5/8 to 3/4 inches.In summary, this is a phenomenal filter for value, quietness, safety for my fish (not snails, shrimp, baby fish, etc.) and flow (works for my 75-gallon). I might order a second one as a backup.