Emperor 400 Power Filter - Up to 80 gal.

Not my favorite. Many reviews love it. I had for a week and have replaced with an AC 70 that is much quiter and smaller. I may have been able to fix the sound a little on the Emporer if I would have tried a little more. The AC's are no work.

I bought this beast for my 30gal tank. If you like the rushing water sound then keep your tank a little low. If not keep the water level at the top and no sound at all. Going on a year and no prob.

Hard to find a power filter with this high of a GPH rating.

Not as good as canister filters but great for a hang on back filter. I have 1 on my 75 gallon aquarium with 1 14 inch oscar cichlid. I don't use the activated carbon, I use sponges and filter pads. It is like the Deenn of HOB filters... Most HOBs are meant for smaller aquariums but not empors... I am considering getting an empoer or penguin 350 for my 120 to be my secondary filter beacause I only have 1 big canister filter on it(xp3 from api)... In conclusion empoer 400 filters are great and for my smaller aquarium I use marineland penguins wich are also great filters...

I have used penguin filter for years, and the emporers since they came out. I didn't like the early emporers, as they were difficult to prime, but decided to try the newer version 400 on my new 75 gallon planted. Priming problems seem to be gone completely with the new two impeller design!
The best bio filters alternate the media between water and air, and that is exactly what the biowheels do. The last emporer 400 I had lasted longer than the pink tilapia it took care of, a monster of a 16" messy as heck tilapia, who lasted 16 years after I rescued him! I depend on Marineland filters, as do most of the best aquarium stores I go to.

Just wish I could replace the mangnito motor when it fails, this unit has the motor built in.That way you wouldn't have to toss the whole system out in the trash.

I am impressed with the the overall design and function of this filter. Granted its only been running for a short while. Its not terribly loud, though noisier than my fluval50 filter. I docked one star because a small piece was missing. Right where the pin for one of the wheels rests, so it doesn't spin quite right. I'm not too concerned by that because after the tank cycles and build up begins to occur, the wheels severely slow down. Sometimes they may not even spin at all (according to the the manual) so I decided to keep it regardless.

Excellent filter system. Been using the Emperor 400 for close to 15 years. Great upgrades over the previous prototype. Use on both Marine and Freshwater systems and would not consider any other hang on filter. For the money, you can't do any better.

Canister systems are great but the prices are way way way too high. Emperor is still the best bang for the buck.

I have seven tanks. The tanks with Bio Wheel are perfect chemically and healthy. Aqua Clear tanks are a step below and require more water changes. Tetra tank sucks and will be getting an Emporor this week.

Been using this filter for many, many years. Will run any marine tank as a stand alone. Full benefit of a wet dry bio system. A great mechanical and chemical filter system also. Element changes are a breeze. Chemical media baskets serve many uses. Also allows you to go on vacation worry free. Job well done!!!!!!!

I had one for over 25 years. I replaced the bushings and impeller once. I only replaced the unit because it was very crusty, it worked fine however. The new one I bought was made not nearly as well, lacking the windows, cheaper plastic, and no replacement bushings. I got 2 years out of it then it started having problems with pumping. The first one cost the same as the new one, go figure.