I was running the Fluval 306 canister and the Aqueon Quiet Flow 20 together on my 27gal cube tank. My tank is over stocked, but with small fish. It's my daughters tank in her room. I could never keep the water clear without add some chemical to the water every few days. I was using Acurel-F to clear up the water and it did work, but like I said I would have to use it every few days. I got the SunSun JUP-01 and installed it in the tank right away. I really didn't pay any attention to the tank for the rest of the day. Installed it around 2pm and got my daughter ready for bed at 8pm the water was a lot clear. The water always has a little cloudiness in it. Not a green tint. With the LED lights you can see if the water has any milky cloud in it easily. This morning I got my daughter ready for school and fed the fish and wow the water was clear. The only thing is I wish this had a water flow control to slow it down a little. 27gal cube the water flow of this thing is close to the output of my Fluval 306 canister. 18 fish in a fresh water 27gal tank and they don't look like they are being blown around. The air valve is kind of useless to have. It will blow air into the tank, but it makes a lot of small bubbles that float around all over the tank. In mot sure why that is an added feature. Another thing is the suction cups. They should have made tabs to easily remove the JUP-01 suction cups from the glass. When it's stuck to the glass, it's stuck to the glass. Not easy to remove. But all in all I have to say, it works.. For how long, who knows.UPDATE... Its been about a week now or better. I use to have to do a 25% or 50% water change a week when cleaning the tank. Looks like I don't have to do a thing to it now. Water is very clear. I don't see any reason to vacuum the rocks. My tank is over stocked and between the Fluval 306 and the SunSun looks like my tank is now stable. The SunSun is still working, I see the little window to check the light and its still on.Another UPDATE... Well the SUNSUN still works, but my daughter wanted a few more fish. I started watching the tank a little more and seen the fish were being blown around a little. I unplugged the SUNSUN and seen yeah it is the output is a little too much. Maybe my tank is too small for the water flow that is coming out of the SUNSUN. My tank is 20x20x20x20 in size, 27 gallon cube. On a 20gallon long or tall might be better for the SUNSUN. Like I said I wish it had a water output adjustment on it. Nothing wrong with the SUNSUN JUP-01. I bought the Aquatop UVE-9 because it has a water flow adjustment. I might get another tank and still use the SUNSUN on that.